More references for
quantum mechanics
I found it helpful to
look at several books besides Dirac's and Feynman's, notably
A. Messiah: Quantum Mechanics
L. Schiff: Quantum
Mechanics,
Landau-Lifshitz, Vol.3,
R.Shankar: Principles of Quantum Mechanics,
Cohen-Tannoudji: Quantum Mechanics,
v. Neumann: Mathematical Foundations of Quantum Mechanics
(etc.)
because in most books you will encounter oddities (often due to the
presentation rather than the subject matter itself) which possibly
another author can explain better.