Naming convention question #names


I have found information about Stefan Uzdansky in Russian and the explanation is that his father had two names Lazar and Tadeush. 

So Tadeushevich is Stefan's second patronymic.

Lara Tsinman

Steven Usdansky

I'm curious as to the naming conventions that might be relevant as I try to determine if I might be related to a Warsaw-born Russian military officer and spy. His name is variously given as (using  Romanized forms) (1) "Stefan Lazarevich Uzdansky", (2) "Stefan Lazarevich Uzdansky (Tadeushevich)", and (3) "Stefan Lazarevich Uzdansky-Jelenski". No questions regarding #1,and it's the most common form used for his name. Regarding #2, where would (Tadeushevich) have come from? It's always given in parentheses in any document that uses it. Regarding #3, would Uzdansky have been one parent and Jelenski the other, and, if so, which would likely be Lazar's surname?

Steven Usdansky
USDANSKY (Узданский): Turec, Kapyl, Klyetsk, Nyasvizh, Slutsk, Grosovo
SINIENSKI: Karelichy, Lyubcha, Navahrudak
NAMENWIRTH: Bobowa, Rzepiennik
SIGLER: "Minsk"