I was doing some research for my EE related to the Auteur theory and I found a really helpful extract of Andrew Sarris's notes on Auteur theory which are annotated and underlined, so you get the main thesis of Andrew Sarris's auteur theory.
That's great Jun. Sarris is such an important figure in US film history as he popularised and critiqued the importance of auteurism leading into the fierce debates about authorship in the 70s.