I recently interviewed for a research job and I listed my current supervisor as a reference after asking her permission. She did agree but she said it was hospital policy to not give a recommendation and she can only verify that I have worked there. Well I thought I had no other choice. Now that I think about it, I could have listed a person who is also my supervisor but works under the first person mentioned. How should I tell the job that I am interviewing for about this replacement reference? Should I just write something like "For an additional reference please call..." in the post interview thank you letter? Thanks so much for the advice, I really need this job! Any advice is appreciated.