I have been learning QFT as a self studier and for my first book, I used Lancaster and Blundell, in it I mostly did second quantization, scalar quantum field theory and tree level scattering and some Feynman diagrams for the scalar level only. Then, I decided to start a new book for fermions, and QED, so I chose Klauber’s Student Friendly Quantum Field Theory. I am nearly done with that book so I was wondering what book should I move onto next, or whether I should even do another book? #science source