Citation, Documentation of Sources

Q. Hello, I would like to know how to handle citations to books that list a subsequent printing date. Some books will say, for example, “Copyright 1975” and elsewhere on the copyright page will list the various printing dates, such as “2nd printing 1979, 3rd printing 1985, 4th printing 1992.”

Should my references point to the original copyright date, or the subsequent printing date? I have searched in vain to find a definitive answer to this or any concrete examples. Thank you very much for the help!

A. Use the copyright date as the publication date in your citation. Printings after the first may include minor corrections but are otherwise intended by publishers to be substantially the same as earlier printings.

In the rare case that you are relying on a portion of the text that’s changed from one printing to another—and you happen to notice the discrepancy—​mention the situation in your text or in a note. For example, “This citation relies on the fourth printing of Smith’s book; the first three printings refer, incorrectly, to the British Museum rather than the British Library.”

Note that a numbered printing (or impression) isn’t the same as a numbered edition, the latter of which must always be cited (see CMOS 1.26 and 14.113).