Thanks very much for your responses. I deliberately did not limit my query to one geographic area because I wanted a broader answer, not being sure at this point how, when or where I am going to go about looking. As it happens, Dean's suggestion of the University of Chicago is particularly apt. Also, by the way, I don't put my name on queries to the List, not because I want to be mysterious but because I don't want anyone 'googling' on my name to pick up everything I have ever said here via the Internet archive.