I would like to credit a reviewer who made a very nice corollary to the paper he was reviewing. Is there any more or less common standard of quoting MathReviews? I would be most grateful for an example of how to do it.
The question seems trivial. Since everyone uses electronic version nowadays, why don't you write just Author, Review of, MR number. If the journal editor will want to edit this, let her edit. I quoted a Zentralblatt review once like this:  H. Schmidt, Zentralblatt fur Math. 27 (1943), 309-311. (This was in pre-computer era).