Chicago-style (notes and bibliography system) is frequently used in History, as its use of footnotes/endnotes in addition a bibliography is useful for emphasizing precise source origins, which is often essential to historiography.
The basic format consists of a number that is assigned to a particular fact in the text, and a footnote with the corresponding number appears at the bottom of the same page, listing the source of the text. At the end of the paper, there is a bibliography (in alphabetical order by author's family name) detailing all the sources that have been cited in the paper, along with other works that were consulted but not directly cited.
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