↑ Volker Kluge : Olympic Summer Games. Die Chronik II. London 1948 - Tokyo 1964. Sportverlag Berlin, Berlin 1998, ISBN 3-328-00740-7 , p. 462 ff .: Due to the time advantages when turning, the majority of the previous records came from competitions in a 25-meter Pool. On the one under 1956 Olympics conducted FINA -Congress was finally determined that records from May 1, 1957 found only on the long course (50 meters or 55 yards) official recognition. Previously dated (long-course) top marks - primarily achieved in Melbourne's Olympic basin - were subsequently recognized as the first official 50-m-course world record if they were no longer undercut on the short course by the specified date.
The men's 200 meter butterfly at the Summer Olympics