When I took a course in NASTRAN in 1990, there was this big, green hardcovered book that had all the answers. Of course, it was out of print, only one copy was available. We learned off bad photocopies and the online info on the VAX. Ouch!
Anyway, Macneal-Schwendler is very much a live and well and supports NASTRAN, their child:
The best source that I've seen is the book by Richard MacNeal (co-founder of MSC), "Finite Elements: Their Design and Performance." This is published by Marcel Dekker, and was written in 1994. If you are in the USA, this is available from the SAE (
for $29. MacNeal gets into the details of how plate and solid elements are really implemented, well beyond the simple basics presented in the classical texts.