in 1945 four young players formed a string quartet called the moscow conservatoire quartet. mstislav rostropovich was the cellist, rostislav dubinsky and nina barshai played the violins and rudolf barshai played the viola. however, after a couple of weeks rostropovich found he was too busy, so he suggested that berlinsky should take his place. the four players that now formed the quartet signed an oath that they would be loyal and stay together as a group. they signed the oath with their own blood. valentin often showed this piece of paper to people. for 60 years he kept a careful record of all the concerts they played. they called themselves the borodin quartet after the composer alexander borodin.