References to the use of Digenea simplex as a anthelmintic, before 1997. In the books:
•Beaarud. T. and Sorensen. N. A, Second international seaweed symposium. London: Pergamon press 1955, p. 171
•Arasaki, S. & Arasaki, T. Vegtables from the Sea, Toyko; Japan Publications, 1983, p. 31