this is an excellent book, very well-researched and (I'm obsessed with this nowadays) cited. Much of th research cits secondary sources, but these are well documented so you can check them in context and disagree with them if you like.
Importantly, he focuses a lot on the idea that Robot Monster is a depiction of a dream, but doesn't explore this fully.
It also includes the original script for RM, though for some reason it's in PDF or something format the Kindle won't read!
Wll worth the read for anyone interested in the movie who thinks sit has been much and unjustly maligned.