John XXI (pope)
John XXI, d. 1277, pope (1276–77), a Portuguese named Pedro Giuliano; successor of Adrian V. Known generally as Peter of Spain (Petrus Hispanus), he is the only Portuguese pope. Peter's reputation as a scholastic philosopher was widespread, and he was the reputed author of an extensively used book on logic. Nine months after his election the ceiling of his library at Viterbo fell and killed him. Due to confusion in the medieval listing of popes named John, he called himself John XXI instead of John XX; this numbering is usually maintained. He was succeeded by Nicholas III.
"John XXI (pope)." The Columbia Encyclopedia, 6th ed.. . Encyclopedia.com. (January 21, 2018). http://www.encyclopedia.com/reference/encyclopedias-almanacs-transcripts-and-maps/john-xxi-pope
"John XXI (pope)." The Columbia Encyclopedia, 6th ed.. . Retrieved January 21, 2018 from Encyclopedia.com: http://www.encyclopedia.com/reference/encyclopedias-almanacs-transcripts-and-maps/john-xxi-pope
Encyclopedia.com gives you the ability to cite reference entries and articles according to common styles from the Modern Language Association (MLA), The Chicago Manual of Style, and the American Psychological Association (APA).
Within the “Cite this article” tool, pick a style to see how all available information looks when formatted according to that style. Then, copy and paste the text into your bibliography or works cited list.
Because each style has its own formatting nuances that evolve over time and not all information is available for every reference entry or article, Encyclopedia.com cannot guarantee each citation it generates. Therefore, it’s best to use Encyclopedia.com citations as a starting point before checking the style against your school or publication’s requirements and the most-recent information available at these sites:
Modern Language Association
The Chicago Manual of Style
American Psychological Association
- Most online reference entries and articles do not have page numbers. Therefore, that information is unavailable for most Encyclopedia.com content. However, the date of retrieval is often important. Refer to each style’s convention regarding the best way to format page numbers and retrieval dates.
- In addition to the MLA, Chicago, and APA styles, your school, university, publication, or institution may have its own requirements for citations. Therefore, be sure to refer to those guidelines when editing your bibliography or works cited list.