Source: cirosantilli/an-introduction-to-quantum-field-theory-by-peskin-and-schroeder-1995
= An Introduction To Quantum Field Theory by Peskin and Schroeder (1995)
https://www.amazon.co.uk/Introduction-Quantum-Theory-Frontiers-Physics/dp/0201503972
This is very widely used in courses as of 2020, it became kind of the default book.
Unfortunately, this approach bores <Ciro Santilli> to death. Or perhaps is too <the missing link between basic and advanced>[just advanced for him to appreciate]. Either of those.
800+ pages.