I've had people tell me to read all of my references before the viva, I didn't have the time to, I have read them all throughout my PhD at some point, all except one, I'm thinking I might get asked about this. I had written something like "B[1] did blah blah blah as discussed in C[2]" it will be obvious I hadn't read this paper but I just couldnt find it anywhere, it doesnt seem to be in print at all, it is quite an old paper, from the 60s. Today I'm concentrating solely on the thesis and writing up a document with all the typos/cut and paste errors in my thesis, I feel I know my thesis but the references is in the back of my mind (down)