Gustaaf Willem
Baron van Imhoff, Dutch governor of Ceylon and the Dutch West Indies
Gustaaf Schlegel
Dutch sinologist
Gustaaf Adolf van den Bergh van Eysinga
Dutch theologian
Gustaaf Adolf Frederik Molengraaff
Dutch geologist and explorer
Gustaaf Deloor
Belgian cyclist
Gustaaf Sorel
Belgian painter
Gustaaf Van Roosbroeck
Belgian cyclist
