@bubbline for entity data, i would recommend Scott Bilas old presentation, you can find it here: https://en.m.wikipedia.org/wiki/Entity_component_system
It's from the time before ECS meant data oriented design, and i think it has a point on composition and data inheritance that is a bit lost on the new ECS stuff.
Luxe engine blog has a bunch of articles on their entity system. Unity has some low level presentations on their system, and i think Rune blogged something about it too https://runevision.com/