@book{gerb:jfak99,

editor="Jelle Gerbrandy and Maarten Marx and Maarten de Rijke and Yde Venema",
title="JFAK. Essays Dedicated to Johan van Benthem on the Occasion of his 50th Birthday",
publisher="Amsterdam University Press",
series="Vossiuspers",
address="Amsterdam",
year="1999",
note="ISBN 90 5629 104 1",
}