In set theory, any element of a partially ordered setP which is greater than or equal to every element of a given subset S of P is called an upper bound of S.
... (1965-1979)
February 11 - Sir Keith Holyoake, New Zealand Prime Minister (1960-1972)
February 20 - Alexei Kosygin[?], Premier of the Soviet Union[?] (+ 1980)
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