Skip to main content
Select Source:

Fersman, Aleksandr Evgenievich

Fersman, Aleksandr Evgenievich

(b. St. Petersburg, Russia, 8 November 1883; d. Sochi, U.S.S.R., 20 May 1945)

mineralogy, geochemistry.

Fersman’s father, Evgeny Aleksandrovich Fersman, was an architect and later a soldier. The atmosphere of his home, which encouraged both art and thought, was unusual in the military environment of that day. Fersman’s mother, Maria Eduardovna Kessler, was a talented pianist and painter; her brother, A. E. Kessler, who studied under the well-known chemist A. M. Butlerov, was also an important influence on the boy’s education.

The Fersman family usually spent the summer holidays on Kessler’s estate near Simferopol, and there, in the Crimean mountains, young Fersman was attracted to mineralogy and began his first mineral collection. The development of his interests was furthered by a trip to Czechoslovakia, to which the family was obliged to go because of the mother’s illness. There, in Karlovy Vary (Carlsbad), an old mining area that was no longer prosperous, he could purchase crystals and druses to fill out his mineral collection. Thus, by the time he graduated from the Odessa Classical Gymnasium in 1901, with a gold medal, Fersman’s interests had already been formed; he was very much interested in mineralogy, he had a good mineralogical collection, and he had accumulated a substantial store of personal observations.

In Novorossisk University, which Fersman entered, the lecture course in descriptive mineralogy was extremely boring, and Fersman at first wished to give up mineralogy and study the history of art instead. Friends of his family, Professor P. G. Melikashvili and the chemist A. I. Gorbov, advised him to give up this idea and to study the structure of matter and questions of molecular chemistry. To B. P. Veynberg, a student of D. I. Mendeleev and a specialist in physical chemistry, Fersman owed his acquaintance with ideas on the nature of crystalline substances, such as ice and frost patterns.

In 1903 Fersman’s father was given command of the First Moscow Cadet Corps, and the son transferred to Moscow University. Here he approached the head of the department of mineralogy, V. I. Vernadsky, who found him a place in his laboratory. There Fersman mastered the goniometric method of measuring crystals. He worked persistently, and while still a student (1904-1907) he published his first seven scientific works, devoted to crystallography and the mineralogy of stolpenite, gmelinite, and other substances.

When Fersman graduated from the university in 1907, Vernadsky retained him in his department to prepare to become a professor. In 1908 Fersman worked in Victor Goldschmidt’s laboratory at Heidelberg University, where he perfected his crystallographic and optical methods. He was commissioned by Goldschmidt to make a tour of the most important jewelers of western Europe and select the most interesting crystals of natural diamonds for study. In Frankfurt, Hanau, and Berlin tens of thousands of carats of diamonds were displayed before him on special tables. As a result of these observations Goldschmidt and Fersman wrote a joint monograph on the crystallography of the diamond (1911) that is still significant.

At Heidelberg, Fersman attended Rosenbusch’s lectures on petrography. In France he visited Lacroix’s laboratory in Paris and made a trip to study the pegmatites of the islands in the Elbe. This trip played a large role in determining his scientific interests, for Fersman later dedicated many years to research on pegmatites.

In 1912 Fersman became senior curator in the mineraiogical section of the Geological Museum of the Russian Academy of Sciences. In the same year, for the first time he gave a course in geochemistry at Shanyavsky University in Moscow. He also took part in the organization of a popular scientific journal, Priroda, to which he gave considerable attention throughout his life. In it he published major articles and notes on geochemistry and mineralogy, diamonds, alloys of radium, emeralds, zeolities, platinum, gases, and other useful minerals found in Russia and other countries.

In 1914 the first period of Fersman’s scientific activity came to a close, when his great gift for and inclination toward scientific synthesis and theoretical generalization became apparent.

At the beginning of 1915 a commission was organized in the Academy of Sciences for the study of the natural resources of Russia, and Fersman was elected scientific secretary. In connection with the work of the commission he studied the deposits of various useful minerals in the Crimea, Mongolia, Trans-Baykal, the Urals, the Altai, and various regions of European Russia.

During World War I, Fersman traveled to the front and compiled geological maps showing the location of construction materials and water-bearing and waterproof horizons, knowledge of which was important for successful military operations. During this period Fersman faced, in the broadest form, the problems of use of mineral raw materials. He was interested in economics and technology, as well as in mineralogy and geology.

Soon after the Russian Revolution, Lenin turned to the Academy of Sciences for definitions of the new problems facing science. He talked with Fersman, who was impressed with his concern for efficient placement of industry nearer to mineral raw materials and for guaranteeing the Soviet Republic a domestic supply of raw materials. All this awakened Fersman’s interest and influenced the direction and planning of his scientific research.

In 1919 Fersman was elected to the Academy of Sciences and was chosen director of its mineralogical museum. Besides imparting his own enthusiasm for science to his students and colleagues, he was modest and encouraged the progress of other researchers. In the winter of 1919-1920 Fersman gave a course of lectures at Petrograd (now Leningrad) University on the geochemistry of Russia, and in the following year repeated it at the Geographical Institute of Petrograd.

Fersman made sizable contributions to the solution of an important theoretical problem of geochemistry: the frequency of distribution of the chemical elements in the rocks of the earth’s crust (clarkes). The term “clarke” (the concentration of an element in the earth’s crust) was proposed by Fersman in honor of the American scientist F. W. Clarke, one of the first to consider this problem in his fundamental work, The Relative Abundance of the Chemical Elements (1889). Fersman calculated the clarkes for most of the elements. Before Fersman, clarkes were expressed in weight percentages. He showed that for geochemical purposes the atomic percentages were more important, thus introducing into science the concept of “atomic clarkes.” As a result he discovered the independence of geochemical abundances from the positions of the elements in the periodic system and the concentration and depletion of the various elements. He showed that abundances within the earth’s crust were determined by the effects of the migration of the elements, while abundances in space were related to the stability of the atomic nucleus. He was the first to consider the problem of regional geochemistry and the division of European Russia into geochemical districts, and he provided a classification of hypogene processes. An expanded course of these lectures was published in 1922.

Fersman published the monograph Dragotsennye i tsvetnye kamni Rossii (“Precious and Colored Stones of Russia,” 1920), as well as works on feldspar, fuller’s earth, and saline mud.

Noteworthy among his numerous investigations and expeditions in the 1920’s and 1930’s is his work in the Khibiny Mountains (Kola Peninsula). He first traveled to the Khibiny Mountains in May 1920, as a member of the commission of the Murmansk railroad, which was headed by the president of the Academy of Sciences, A. P. Karpinsky, and the geologist A. P. Gerasimov. Fersman later expended much of his creative energy in the study of the Khibiny Mountains. He led many expeditions, and his research enabled him to combine separate facts and observations into a coherent system providing an integrated view of the formation processes of the geological structures of the Fenno-Scandinavian shield.

The mineralogical and geochemical research in the Khibiny was crowned by the discovery of great deposits of apatite. Fersman was not only a scientist but also the developer of this inhospitable region. At his initiative the Khibiny mining station was opened in 1937, and Fersman was its first director. This station later grew into an important scientific institution: the Kola branch of the Soviet Academy of Sciences.

Fersman’s study of central Asia began in 1924 and continued until the 1940’s. At the beginning of his work it was believed that central Asia had few deposits of useful minerals. He carried out considerable scientific research to show the mineral riches there and thus refuted that erroneous belief. Fersman discovered in the Karakum Desert deposits of virgin sulfur; with his help a sulfur refinery was built on the site of the discovery and has supplied the Soviet Union with sulfur ever since.

In the Urals, Fersman investigated pegmatite, rare elements, and deposits of copper, chromium, and other useful minerals. In Siberia he began research showing the value of further study and the great richness of the deposits there. Fersman wrote the important works Geokhimicheskie problemy Sibiri (“Geochemical Problems of Siberia”) and Geokhimicheskie problemy Soyuza (“Geochemical Problems of the [Soviet] Union,” 1931).

During World War II, Fersman was concerned with military geology and problems of securing strategic materials. He headed the Commission for the Geological-Geographical Services of the Red Army, to which he attracted many important specialists. He traveled to the front many times with reports and lectures on strategic materials and military geology. In this period he wrote several books and articles on strategic materials of the Soviet Union and Germany, and by comparing them showed that the Soviet Union’s military potential guaranteed its victory.

Fersman gave much attention to the history of science. He tried to show the origins of scientific ideas and the achievements of researchers, in particular his predecessors D. I. Mendeleev and V. I. Vernadsky. With particular warmth he wrote of those who, with him, created the new science of geochemistry and of his teachers Vernadsky, Goldschmidt, and G. Hevesy, among others. Fersman had the ability to write sketches that give clear pictures of scientists. Reading his Zanimatelnaya geokhimia (“Entertaining Geochemistry,” 1948), one can learn of the remarkable work of Marie Curie, A. P. Karpinsky, N. S. Kurnakov, P. I. Preobrazhensky, V. G. Khlopin, and many other distinguished scientists. Through his popular articles, sketches, and books, such as Zanimatelnaya mineralogia (“Entertaining Mineralogy,” 1928), Puteshestvia za kamnem (“Traveling for Rocks,” 1956), Vospominania o kamne (“Recollections About Rocks,” 1940), Rasskazy o samotsvetakh (“Tales of Semiprecious Stones,” 1957), Fersman helped explain the practical significance of theoretical research in geology.

Fersman gave much attention to his students, many of whom became outstanding scientists: D. I. Shcherbakov, A. A. Saukov, V. V. Shcherbina, and O. A. Vorobeva, among others.

For his achievements and services in geochemistry, mineralogy, geology, and geography Fersman was elected member or corresponding member of sixteen scientific organizations and societies in his native country and abroad. He was awarded the Lenin Prize (1929), the State Prize of the U.S.S.R. of the First Degree (1941), medals from the University of Belgium (1936) and the Wollaston Medal (1942), and the order of the Red Banner of Labor.

Fersman was an active leader of the Academy of Sciences of the U.S.S.R., occupying at various times the posts of vice-president, member of the Presidium, academician-secretary of the Section of Mathematics and Natural Sciences, president of the Council for the Study of Natural Resources, and director of publications.

His scientific creativity was characterized by an exceptionally broad scope and an integral view of nature. With a good understanding of the underlying relationships between various phenomena, he was a master of theoretical generalization and scientific synthesis.

Of major significance were Fersman’s works in geochemistry, which he, like his teacher Vernadsky, understood more deeply and more broadly than his contemporaries. According to his definition, geochemistry should concern the history of atoms of chemical elements in the earth’s crust and their behavior under various thermodynamic, physical, and chemical conditions of nature. Fersman showed with great clarity the significance of Mendeleev’s periodic law for geochemistry.

All his life Fersman did research in mineralogy and geochemistry; he showed graphically, vividly, and in a fascinating way that these sciences do not consist of dry ideas, of inanimate, dead objects of nature; rather, they are sciences of the origins and history of natural phenomena, the complex chemical processes that form the face of the earth and that slowly but inexorably transform what appears to be lifeless stone into new chemical compounds. The idea of geochemical character lay at the basis of all his further work, which was closely connected with the study of the useful minerals of the U.S.S.R. It appeared to him that at the foundation of all surrounding life, all surrounding transformations, and even of the very life processes themselves lay the laws of the dispersion and combination of ninety chemical elements, from which the earth and all of space are constructed, and that one cannot, by studying it only in the laboratory, tear lifeless stone away from the great laboratory of nature in which its transformations take place.

In Khimicheskie elementy zemli i kosmosa (“The Chemical Elements of the Earth and Space,” 1923), Fersman extended the problem of the history of the elements to the universe; in Geokhimia Rossii (“Geochemistry of Russia,” 1922) he had tried to apply these ideas to the understanding of those different phenomena which take place in widely distant regions of the U.S.S.R. Most important in Fersman’s work is his constant recurrence to the basic problems posed in the past, introducing the study of chemical processes into the chemistry of space while still taking each element back from space to earth and giving attention to its use by man.

In 1932 Vernadsky, following the publication of the monograph Pegmatity (“Pegmatites”), expressed pleasure with this new and important work, through which scientists have come to a deeper understanding of the world’s structure and of the role of atoms in that structure, about which C. F. Shonbein and Faraday had theorized in the late 1830’s. The periodicity of properties in space pointed to a spiral pattern of phenomena, the more so since for the periodic system the spiral was very important.

Fersman asserted that the whole course of chemical processes in space is simply a great Mendeleevian system, in which the laws of energetics and the level of energy govern separate cells, moving elements and combinations of elements about in time and space. The places of the elements in the periodic system reflected a definite step in the chemical history of earth and the universe, between which there is an inner connection.

Fersman’s ideas frequently were ahead of his time, and in many of his works he foresaw the future, describing future science and technology. In a special sketch in Zanimatelnaya geokhimia attention is drawn to future achievements: the use of atmospheric gases, the ozone screen, the warmth of the earth’s depths, atomic energy, the energy of ocean waves and winds, and of new synthetic carbon compounds, and of man’s penetration into space.

In calling the geochemical activity of mankind “technogenesis,” Fersman meant the economic and industrial activity of man, according to his own scale and significance, compared with the processes of nature herself. Technogenesis basically leads to the extraction of chemical elements from the earth, the redistribution of elements from the depths on the earth’s surface, and the agricultural and engineering regrouping of elements. Analyzing the pattern of use of separate elements, its connection with clarkes, and the role of clarkes of concentration, Fersman showed that man concentrates certain elements (gold, platinumn, silver, and so forth) and disperses others (carbon, tin, magnesium, silicon, and so forth). As a result he defined the basic geochemical relations between man and nature and noted that the laws of geochemistry force man to seek technical solutions in the use of poor lodes with scattered and rare elements. Technogenesis represents a distinguished theoretical and practical achievement of science, especially in the light of contemporary achievements (atomic experiments and space research). Fersman’s work in this area will long light the way for new research, inventions, and the conservation of natural resources.


I. Original Works. Fersman’s writings include Der Diamant (Heidelberg, 1911), written with V. Goldschmidt; Dragotsennye i tsvetnye kamni Rossii (“Precious and Colored Stones of Russia,” Petrograd, 1920); Geokhimia Rossii (“Geochemistry of Russia,” Petrograd, 1922); Puti k nauke budushchego(“Paths Toward the Science of the Future,” Petrograd, 1922);Khimicheskie elementy zemli i kosmosa (“The Chemical Elements of the Earth and Space,” Petrograd, 1923); khimia mirozdania (“The Chemistry of the Universe,” petrograd, 1923); Istoria almaznogo fonda (“History of Diamond Stocks,” Moscow, 1924); Zanimatelnaya mineralogia (“Entertaining Mineralogy,” Letingrad, 1928); Pegmatrity (“Pegmatites,” Leningrad, 1931); Geokhimicheskie problemy Sibiri (“Geochemical Problems of Siberia,” Moscow-Leningrad, 1931); Geokhimicheskie problemy soyuza (“Geochemical problems of the [Soviet] Union” Moscow-Leningrad, 1931); Geokhima (“Geochemistry”),4 vols. (Leningard, 1933-1939); Vospominania o kamne (“Recollections about Rocks,” Moscow, 1940); voynai i strategicheskoe syre (“The War and strategic Raw Material,” Krasnoufimsk, 1940); Geologia i voyna (“Geology and War,” Moscow-Leningrad, 1943); Khimia zemli na novykh putyakh (“The Chemistry of the Earth on New Paths,” Moscow, 1944); Mineralnoe syre zarubezhnykh stran (“The Mineral Raw Materials of Foreign Countries,” Moscow-Leningrad, 1947); Zanimatelnaya geokhimia (“Entertaining Geochemistry,” Moscow-Leningrad, 1948); Ocherki po istorii kamnya (“Essays on the History of Rocks”), 2 vols. (Moscow, 1954-1961). Many of his works were brought together as Izbrannye trudy (“Selected Works”), 7 vols. (Moscow, k 1952-1962).

II. Secondary Literature. On Fersman or his works, see G. P. Barsanov, “Kharakternye cherty tvorchestva akademika A. E. Fersmana i ego raboty po mineralogii” (“Characteristic Features of the Creative work of Academician A. E. Fersman and His Work in Mineralogy”), in Trudy mineralogicheskogo muzeya Akademii nauk, USSR no. 5 (1953), 7-18; R. F. Gekker, “Akademik A. E. Fersman i ego rabota vo Vseroccyskom obshchesve okhrany prirody” (“Academician A. E. Fersman and His Work in the All-Russian Society for the Conservation of Nature”), in Okhrana prirody, no. 3 (1948), 113-119; D. P. Grigoriev and I. I. Shafranovsky, Vydayushchiesya russkie mineralogi (“Distinguished Russian Mineralogists,” Moscow-Leningrad, 1949), pp. 196-233; O. V. Isakova, ed., Aleksandr Evgenievich Fersman (Moscow, 1940), a bibliographical collection; O. Pisarzhevsky, Fersman (Moscow, 1959); and A. A Saukov, “Raboty A. E. Fersmana pogeokhimii” (“The work of A. E. Fersman in Geochemistry”), in Yubileyny sbornik, posvyashenny tridtsatiletiyu Velikoy Oktyabrskoy sotsialisticheskoy revolyutsii (“Jubilee Collection, Dedicated to the Thirtieth Anniversary of the Great October Socialist Revolution”), I (Moscow-Leningrad, 1947), 57-60.

See also I. I. Shafranovsky, “Trydy A. E. Fersman po kristallografii” (“The Work of A. E. Fersman in Crystallography”), in A. E. Fersman. Kristallografia almaza (“A. E. Fersman. Crystallography of the Diamond,” Moscow, 1955), pp. 532-546; D. I. Shcherbakov, “Aleksandr Evgenievich Fersman i ego tvorchestvo” (“Aleksandr Evgenievich Fersman and His Work”), ibid., pp. 490-531; “A. E. Fersman i ego puteshestvia” (“A. E. Fersman and His Travels,” Moscow, 1953); “Osnovnye cherty tvorchestva A. E. Fersmana i drugikh” (“Basic Features of the creative work of A. E. Fersman and others,” in Voprosy geokhimii i mineralogii (“Questions of Geochemistry and Mineralogy,” Moscow, 1956), pp. 1-175; and Aleksandr Evgenievich Fersman. Zhizn i deyatelnost (“Aleksandr Evgenievich Fersman. Life and Work”), of which Shcerbakov was editor (Moscow, 1965).

Other sources include V. V. Shcherbina et al., in Byulleten Moskovskogo obshchestva ispytateley prirody, n.s 51 no.1 (1946), 90-97; O. M. Shubnikova, “Ocherk zhizni i deyatelnosti A. E. Fersman i drugikh” (“Essay on the Life of A. E. Fersman and others”), in Zapiski Vserossyskogo mineralogicheskogo obshchestva, 2nd ser.,75 , no 1 (1946), 55-64; A. V. Sidorenko, “Issledovania A. E. Fersman V Turkmenii i ikh Znachenie” (“The Research of A. E. Fersman in Turkmen and Its Significance”), in Izvestiya Turkmenistanskogo filiala Akademeii nauk USSR, no.1 (1950), 28-39; and N. D. Zelinsky, “pamyati akademika A. E. Fersmana” (“Memories of Academician A. E. Fersman”), in Uspekhi khimii, 14, , no.6 (1945), 463-467.

A. Meniailov

Cite this article
Pick a style below, and copy the text for your bibliography.

  • MLA
  • Chicago
  • APA

"Fersman, Aleksandr Evgenievich." Complete Dictionary of Scientific Biography. . 23 Jun. 2017 <>.

"Fersman, Aleksandr Evgenievich." Complete Dictionary of Scientific Biography. . (June 23, 2017).

"Fersman, Aleksandr Evgenievich." Complete Dictionary of Scientific Biography. . Retrieved June 23, 2017 from

Fersman, Aleksandr Evgenievich (1883-1945)

Fersman, Aleksandr Evgenievich (1883-1945)

Russian geochemist

Aleksandr Evgenievich Fersman was a Russian geochemist and mineralogist. He made major contributions to Russian geology , both in theory and exploration, advancing scientific understanding of crystallography and the distribution of elements in the earth's crust , as well as founding a popular scientific journal and writing biographical sketches of eminent scientists. He was known as a synthesizer of ideas from different subdisciplines.

Fersman was born in St. Petersburg on November 8, 1883, to a family that valued both art and science. His father, Evgeny Aleksandrovich Fersman, was an architect and his mother, Maria Eduardovna Kessler, a pianist and painter. Fersman's maternal uncle, A. E. Kessler, had studied chemistry under Russian chemist Aleksandr Mikhailovich Butlerov.

At the family's summer estate in the Crimea, Fersman first discovered minerals and began to collect them. When his mother became ill, the family traveled to Karlovy Vary (Carlsbad) in Czechoslovakia. There the young Fersman explored abandoned mines and added to his collection of crystals and druses (crystal-lined rocks).

Fersman graduated from the Odessa Classical Gymnasium in 1901 with a gold medal and entered Novorossisk University. He found the mineralogy course so dull that he decided to study art history instead. He was dissuaded by family friends (the chemist A. I. Gorbov and others) who encouraged him to delve into molecular chemistry. He subsequently studied physical chemistry with B. P. Veynberg, who had been a student of Russian chemist Dmitri Ivanovich Mendeleev. Veynberg taught Fersman about the properties of crystals.

The Fersman family moved to Moscow in 1903 because Aleksandr's father became commander of the First Moscow Cadet Corps. Fersman transferred to Moscow University, where his interest in the structure of crystals continued. Studying with mineralogist V. I. Vernadsky, he became an expert in goniometry (calculation of angles in crystal) and published seven scientific papers on crystallography and mineralogy as a student. When Fersman graduated in 1907, Vernadsky encouraged him to become a professor.

By 1908, Fersman conducted postgraduate work with Victor Goldschmidt at Heidelberg University in Germany. Goldschmidt sent him on a tour of Western Europe to examine the most interesting examples of natural diamond crystals in the hands of the region's jewelers. This work formed the basis of an important monograph on diamond crystallography Fersman and Goldschmidt published in 1911.

While a student in Heidelberg, Fersman also visited French mineralogist François Lacroix's laboratory in Paris and encountered pegmatites for the first time during a trip to some islands in the Elbe River that were strewn with the rocks. Pegmatites are granitic rocks that often contain rare elements such as uranium, tungsten, and tantalum. Fersman was to devote years to their study later in his career.

In 1912, Fersman returned to Russia, where he began his administrative and teaching career. He became curator of mineralogy at the Russian Academy of Science's Geological Museum. He would be elected to the Academy and become the museum's director in 1919. During this period Fersman also taught geochemistry at Shanyavsky University and helped found Priroda, a popular scientific journal to which he contributed throughout his life.

Fersman participated in an Academy of Science project to catalogue Russia's natural resources starting in 1915, traveling to all of Russia's far-flung regions to assess mineral deposits. After the Russian Revolution, Lenin consulted Fersman for advice on exploiting the country's mineral resources. During World War I Fersman consulted with the military, advising on strategic matters involving geology, as he would also later do in World War II.

In the early 1920s, Fersman devoted himself to one of geochemistry's major theoretical questions regarding the distribution of the chemical elements in the earth's crust. Fersman worked out the percentages for most of the elements and proposed that these quantities be called "clarkes" in honor of Frank W. Clarke, an American chemist who had pioneered their study. Clarkes had traditionally been expressed in terms of weight percentages; Fersman calculated them in terms of atomic percentages. His work showed different reasons for the terrestrial and cosmic distribution of the elements. He was interested in the ways in which elements are combined and redistributed in the earth's crust. He coined the term "technogenesis" for the role of humans in this process, concentrating some elements and dispersing others through extraction and industrial activities.

Over the next twenty years, Fersman was responsible for a reassessment of the U.S.S.R.'s mineral resources. There were many areas, such as Soviet Central Asia and Siberia, which were thought to be resource-poor. Fersman showed otherwise, traveling from the Khibiny Mountains north of the Arctic Circle near Finland to the Karakum Desert north of Iran. He found rich deposits of apatite (a phosphorus-bearing mineral useful in fertilizers) in the former and a lode of elemental sulfur in the latter.

Fersman was acutely aware of the history of his profession and of science in general, passing on to his students his respect for his predecessors, especially Mendeleev and Vernadsky. He wrote many biographical sketches of distinguished scientists and published a number of popular works on mineral collecting. He was active in the Academy of Science of the U.S.S.R., serving in five different administrative posts, and received a number of honors, including the Lenin Prize. He died in the Soviet Georgian city of Sochi on May 20, 1945.

See also Earth, interior structure; Mineralogy

Cite this article
Pick a style below, and copy the text for your bibliography.

  • MLA
  • Chicago
  • APA

"Fersman, Aleksandr Evgenievich (1883-1945)." World of Earth Science. . 23 Jun. 2017 <>.

"Fersman, Aleksandr Evgenievich (1883-1945)." World of Earth Science. . (June 23, 2017).

"Fersman, Aleksandr Evgenievich (1883-1945)." World of Earth Science. . Retrieved June 23, 2017 from