= Advanced quantum mechanics by Freeman Dyson (1951)
{c}
https://arxiv.org/abs/quant-ph/0608140v1
Lecture notes that were apparently very popular at <Cornell University>. In this period he was actively synthesizing the revolutionary bullshit <Richard Feynman> and <Julian Schwinger> were writing and making it understandable to the more general <physicist> audience, so it might be a good reading.
\Q[We shall not develop straightaway a correct theory including many particles. Instead we follow the historical development. We try to make a relativistic quantum theory of one particle, find out how far we can go and where we get into trouble.]
Oh yes, see also: <Dirac equation vs quantum electrodynamics>.