Subscribe to The Chicago Manual of Style Online
Quotations and Dialogue
Q. I cannot find any advice in section 6.99 about how to handle completion of abridged matter when providing the missing letters in brackets. For instance, if the original has “P. Jarnach,” should one write “P.[hilipp] Jarnach” or “P[hilipp] Jarnach”? In other words, should one keep or drop the period? My practice has always been to omit it because it is obvious that there was one and because keeping it would look crowded.
A. In clarifying quoted text, brackets can be used not only to comment on the original text but also to replace it. In this case, the period in the original literally stands for the rest of the abbreviated name and can be replaced (so “P.” becomes “P[hilipp]”). Another option would be to supply the name after the initial, leaving the initial and period intact: “P. [Philipp] Jarnach.” But your practice of replacing the period is more elegant and gets Chicago’s seal of approval. You’ll find an example of this usage at CMOS 14.74.