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Citation, Documentation of Sources
Q. When doing footnotes, do you put a footnote after every sentence, even if two or more consecutive sentences are from the same source and same page? Or can it be assumed that, regardless of the punctuation (as long as it is in the same paragraph), all that came after the last citation and before the footnote you just inserted is part of the same source and same page?
A. Footnotes should be placed where you need them, not according to a rule. Whenever you can imagine the reader asking “Says who?” you should add a note. It’s not true that the reader can assume that everything between one footnote and the next is attributable to the first source, since most writers interject their own arguments or conclusions between the borrowed materials. If everything in a paragraph is from the same source, however, it’s enough to put one note at the end of the paragraph.