Mineralengids mineralen, gesteenten, edelstenen

by Duda, Rudolf, Rejl, Lubos, Kuipers, Niko
Published 2003

Mysteries en wonderen van de natuur met internetlinks

by Dalby, Elizabeth, Tatchell, Judy, Kuipers, Niko, Brown, Carla
Published 2005

Papier in Japan

by Buisson, Dominique 1947-, Kuipers, Niko, Engelse, P.M. den
Published 1993