I am asking this question to get further perspective on an issue that has come up with a student (undergraduate, mathematics) I am mentoring. At last summer's REU he wrote (in particular!) a solo paper. I was not directly involved with the research, but I gave him some feedback on the writing before he submitted it for publication a few months ago. He has now received a referee report, which is very positive and is of the sort that I would recognize as being 99% likely to lead to acceptance. The referee requests revisions, many of which I agree with.
However, one of the referee's suggestions is for the student to not explicitly state two well-known theorems that he is making use of. (In case it helps to know, these are Dirichlet's Theorem on primes in arithmetic progressions and Minkowski's Convex Body Theorem.) The referee follows up by saying that even if he does want to state them, he should not give citations to them, since they are so well known and google searches easily turn up references.
(1) How would you respond to this referee request if you were the author?
(2) How would you advise a young student to respond to this request?