On the male copulatory organ of some Polycystididae and its importance for the systematics of the family
Schockaert, E.R. (1974). On the male copulatory organ of some Polycystididae and its importance for the systematics of the family, in: Riser, W. et al. (Ed.) Biology of the Turbellaria. pp. 165-172
In: Riser, W.; Morse, M.P. (Ed.) (1974). Biology of the Turbellaria. McGraw-Hill: New York. ISBN 0-070-52947-7. XXV, 530 pp., meer
