Background
Gerretsen, Johannes Cornelis was born on September 17, 1945 in Groningen, The Netherlands. Son of Johannes Cornelis and Clasina Helena Gerretsen.
Gerretsen, Johannes Cornelis was born on September 17, 1945 in Groningen, The Netherlands. Son of Johannes Cornelis and Clasina Helena Gerretsen.
Director audio visual department State University, Groningen, The Netherlands, since 1963.
Married Didy Han, August 8, 1969. Children: Marcella, John.