Charles a few things.
You do not need to be in the US to read a Google Book. There is a thing called proxy or super proxy or something of that sort, which will mask where you are, and thus allow anyone to read a book as if they were in the US.
Secondly I like the idea of asking Google Books to specify what sort of citation THEY would like a person to use. In lieu of that, there is a standard form of citation to include the repository in which you found the item, as well as the item itself. I think though, 99.34% of our writers probably will continue to use the simplest form possible. In fact we have a robot just to help fill out bad citations. When I find them, I tend to make these citations fuller myself, but it's a never-ending task.
Will