Sheet music

Mr.Ma,

I love how do u play cello, and also I play cello too, and I'm Chinese too.

I have been watched a video of urs a very old concert, here's the website: http://www.youtube.com/watch?v=bc2RsoJ0ljc

I want to know how did u get the sheet music of this, I'm very interesting to play this.

Sicerely,
David Sheng