12:33 AM
@Thorgott There isn't actually a ton there, though the inference I draw is that "This follows from (2.65))" is the preferred style (note that is just "(2.65)", not "equation (2.65)").
> Identifying letters ((a), (b), (c)), including their parentheses, are roman in all text. The AMS will allow italic identifying letters only if consistent throughout.
> In cross-references, equation numbers are enclosed in roman parentheses to match the original label and the parentheses are always roman.
(which only says that equation numbers should always be in parentheses, not other kinds of braces).
On the other hand, the only references that the style guide has to brackets is in the context of citations and "fences" in mathematical contexts. I do not think that AMS editors would be too happy with square braces for parenthetical content.
Personally, I would seek to rewrite the phrase.
@Obliv No. This is wrong. Again, see section 13.14 of the AMS style guide.