1. Some aspects of respiratory physiology of three South African freshwater snails Bulinus (Physopsis) africanus (Krauss), Bulinus (Bulinus) tropicus (Krauss) and Lymnaea natalensis (Krauss);Alberts LE;S Afr J Sci,1966
2. Ecologia: In Monograph on Schistosomiasis mansoni;Andrade RM;Rev Bras Malar,1959
3. Review of literature on abiotic fac tors influencing the distribution and life cycles of bilharziasis intermediate host snails;Appleton CC;Malacol Rev,1978
4. The molluscan family Planorbidae;Baker FC,1945
5. Aquatic and aerial respiration in animals;Carter GS;Biol Rev,1931