1. Aldwell, C.R.; Bush, B.: Agriculture and ground water must co-exist. Environ. Geol. and Water Sci. 9, 1?2 (1986)
2. Anderson, H.A.; Belluck, D.A.; Sinha, S.K.: Recommended public health related ground water standards ? 1986; Summary of scientific support documentation for NR 140.10. Wis. Div. of Health, Dept. of Health and Social Services, Madison, Wis. 1986.
3. Anderson, L.J.; Kristiansen, H.: Nitrate in ground water and surface water related to land use in the Karup Basin, Denmark. Environ. Geology 5, 207?212 (1984)
4. Astruc, J.G.; Roche, J.; Soule, J.C.; Tarisse, A.; Vernet, R.: Vulnerabilite des karsts du Quercy: problemes poses par la protection des sources de Touzac, Soturac, Boyssac, Lenclio. Hydrogeologie 3, 297?304 (1986)
5. Baker, D.B.: Regional water quality impacts of intensive rowcrop agriculture: Lake Erie Basin case study. J. Soil and Water Cons. 40,1, 125?132 (1985)