Ola Bratteli
Ola Bratteli (24 October 1946 – 8 February 2015) was a Norwegian mathematician.He was a son of Trygve Bratteli and Randi Bratteli (née Larssen). He received a PhD degree in 1974. He was appointed as professor at the University of Trondheim in 1980 and at the University of Oslo in 1991. He was a member of the Norwegian Academy of Science and Letters. Provided by Wikipedia