https://mathworld.wolfram.com/Non-AbelianGroup.html
Non-Abelian Group -- from Wolfram MathWorld
A non-Abelian group, also sometimes known as a noncommutative group, is a group some of whose elements do not commute. The simplest non-Abelian group is the...
abelian groupwolfram mathworldnon
https://www.numdam.org/item/?id=CM_1972__25_2_135_0
Compact abelian group extensions of dynamical systems II
abelian groupdynamical systemscompactextensions