About IFS : Internal Family System
I like those videos by the creators of the IFS Guide app. They have others, don't hesitate to check their youtube channel.
Some books which have really helped me and that I recommend:
SELF-THERAPY, by Jay Earley
Clear, simple, with lots of drawings: ideal to work on your own system.

WE ALL HAVE PARTS, by Colleen West
Short and clear, with lots of illustrations. A very brief introduction to IFS.

Books by Frank Anderson:
IFS SKILLS TRAINING MANUAL, a step by step clear guide.

TRANSCENDING TRAUMA
To go one step further.

