Used copy of No-nonsense Quantum Field Theory by Jakob Schwichtenberg sold on Pangobooks.
No-Nonsense Quantum Field Theory: A Student-Friendly Introduction
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Ciro Santilli's Homepage
No-Nonsense Quantum Field Theory – No-Nonsense Books
No-Nonsense Quantum Mechanics – No-Nonsense Books
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Quantum Field Theory for the Gifted Amateur eBook
Teach Yourself Physics: a travel companion by Jakob Schwichtenberg
quantum field theory - Wick's theorem and Feynman propagator
Quantum Field Theory, Book hardback