This is simple list of russian names and their variants gathered from different sources.
It is a csv file in format
Name;InvariantName
Елена;Елена
Elena;Елена
Леночка;Елена
Lena;Елена
Ленчик;Елена
Elen;Елена
...
Here Name is a name variation of russian name in russian and english, InvariantName is a basis name.