Welchman was one of the top four mathematicians to be recruited in 1939 to supervise decoding operations at Bletchley Park .
Joan 's mathematical abilities were first discovered by Gordon Welchman , in an undergraduate Geometry class at Cambridge .
Gordon Welchman was Gordon Welchman of the top four mathematicians to be recruited in 1939 to supervise decoding operations at Bletchley Park .
Joan 's mathematical abilities were first discovered by Gordon Welchman , in an undergraduate Geometry class at Cambridge .