the best one will have a thorough undertaking of feedback and give transfer functions for all converters...as well as opto/TL431 feedback transfer functions.
If it does not contain this....and you don't know how to derive transfer functions......then you and i will be on a wing and a prayer with our SMPS's
Anyway, for simple level......i find "power supply cookbook" by brown is good......even simpler is "demystifying swithc mode power supplies" by ...uuuuhh......i think his name is......damned i forget......ahhhh...its Ray Mack Junior.
Chrisstophe Basso contains many transfer functions but not all....for example he does not have OPTO/TL431 when not using output CLC filter.
I hear of a book by Mohamed Rashid buit never seen it.
Also, Mohan....also Cyril Lander but never seen.
Pressman's book i hear lots about but a kind reader from this forum tells me it doesnt have opto/tl431 transfer function
there used to be (probably still is) a superb bookshop in Charring Cross Road in London (Foyles)...it had every book in the world practically and you could go there and find anything..........but then the health & safety people spoilt it by banning their high book-cases as they said they could topple, like a domino effect......now they have much smaller bookcases and nowhere near as many books...........it is a great great shame.