Based on 'Informatie in woord en beeld over' natuurbeheer: zelfmoord of zelfbehoud' by D. Vreugdenhil. Amsterdam: Moussault, 1970.
Bibliography p.57-58. - Includes index.
Conservation by James Whinray. ISBN 0713613149. Published by A. and C. Black in 1973. Publication and catalogue information, links to buy online and reader comments.