In Russian, "a reference in a footnote" and "internal exile" (often as a form of criminal punishment) are the same word, ссылка (ssylka). Odd but true.

Or maybe not so odd, given the root "send"; the footnote sends you to another source, the exile to another city. So remember: Footnotes are the Siberia of your article (and endnotes, I suppose, the Kamchatka).