A manuscript co-written by Albert Einstein on his theory of relativity was auctioned Tuesday for 11.7 million euros ($13 million).
The manuscript was sold by Christie's in Paris to an anonymous buyer.
Christie's said on its website that the 54-page working manuscript, co-written by Einstein and Michele Besso between June 1913 and early 1914 in Zurich, Switzerland, was a crucial stage in the development of the General Theory of Relativity.
