Ulf Merbold and Lodewijk van den Berg, both flew in ?
Lodewijk van den Berg Lodewijk van den Berg (] ; born March 24, 1932) is a Dutch American chemical engineer, specializing in crystal growth, who flew on a 1985 Space Shuttle "Challenger" mission as a Payload Specialist.
Freek van de Graaff Frederik Robbert "Freek" van de Graaff (20 February 1944 – 24 June 2009) was a Dutch rower who won a bronze medal in the coxed fours at the 1964 Summer Olympics. His team mates were Marius Klumperbeek (cox), Lex Mullink, Bobbie van de Graaf and Jan van de Graaff. The three "van de Graaf(f)s" were all born in 1944.