The Magazine Network
The Magazine Network: Géza Perneczky
Monography on alternative art in 1968-1988, mentions Serge Segay, Ry Nikonova, Boris Konstriktor, Transfurism, Transponans and Double mainly on pp. 108-109. It has actually a very good reference section. I also find calling Yeysk "village" priceless, even though Azov sea can't technically be a lake (it connects to the ocean via Black and Mediterranean seas).
“...Rea Nikonova and Serge Segay, who lived in the Russian village of Eysk near the Azov lake.
In fact, these two Russian artists were those who managed to break through the Iron Curtain with their mail art works.
...
What strikes us the most is the emotional and formal richness of these works...”