Servo motor adapters

Yesterday a friend on twitter (@Cleo_Qc) asked me if I had references to servo motor shaft/teeth dimensions. I did not have but a few google search and I found some valuable links and documents:

First this post which outlines the "standard" names used by Hitec servos: https://www.servocity.com/servo-spline-info

This lead me to this post on Robotshop.com which gives details on some attachment standard: https://www.robotshop.com/blog/en/hobby-robot-industry-standards-hubs-patterns-18681

If you have more reference on the subject, feel free to post them in comments below.