1. Selective primary health care;Walsh;N Engl J Med,1979
2. Morbidity and mortality in ascariasis;Pawlowski,1989
3. Sanitation and disease: health aspects of excreta and wastewater management;Feachem,1983
4. Impact of helminth infections on human nutrition;Stephenson,1987
5. Worms and disease;Muller,1975