I think I’ll jot down some ideas here (2,2,4)
I believe the answer is:
in my book
I'm afraid I can't explain this answer.
Can you help me to learn more?
(Other definitions for in my book that I've seen before include "as far as I'm concerned?" , "As I see it" , "To my way of thinking" , "How to describe writer's published words" , "place for autobiographical details" .)