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Helge Arnulf Tverberg -LRB- born 6 March 1935 -RRB- is a Norwegian mathematician .. Norwegian. Norwegian people. mathematician. mathematician. He was a professor in the Mathematics Department at the University of Bergen , his speciality being combinatorics ; he retired at the mandatory age of seventy .. University of Bergen. University of Bergen. combinatorics. combinatorics. Bergen. Bergen. He was born in Bergen .. Bergen. Bergen. He took the cand.real .. degree at the University of Bergen in 1958 , and the dr.philos .. University of Bergen. University of Bergen. Bergen. Bergen. degree in 1968 .. He was a lecturer from 1958 to 1971 and professor from 1971 to his retirement in 2005 .. He was a visiting scholar at the University of Reading in 1966 and at the Australian National University , in Canberra , from 1980 to 1981 , 1987 to 1988 and in 2004 .. University of Reading. University of Reading. Australian National University. Australian National University. He is a member of the Norwegian Academy of Science and Letters .. Norwegian. Norwegian people. Norwegian Academy of Science and Letters. Norwegian Academy of Science and Letters. Tverberg , in 1965 , proved a result on intersection patterns of partitions of point configurations that has come to be known as Tverberg 's partition theorem .. It inaugurated a new branch of combinatorial geometry , with many variations and applications .. combinatorial geometry. combinatorial geometry. An account by Gunter M. Ziegler of Tverberg 's work in this direction appeared in the issue of the Notices of the American Mathematical Society for April , 2011 .. Gunter M. Ziegler. Gunter M. Ziegler