olemus
rühm, mille binaarne tehe ("×") on korrutamine
= a group in which the operation of the group is multiplication

ülevaateid
http://mathworld.wolfram.com/MultiplicativeGroup.html

https://encyclopediaofmath.org/wiki/Multiplicative_group

https://en.wikipedia.org/wiki/Multiplicative_group

https://en.wikipedia.org/wiki/Multiplicative_group_of_integers_modulo_n