Proceedings of the NWWA Western Regional Conference on Ground Water Management : held October 23-26, 1983, Town and Country Hotel, San Diego, California / sponsored by Natl Water Well Assoc ; ed by D.M. Nielsen & L. Aller.
Proceedings of the Fourth Annual Eastern Regional Ground Water Conference : July 14-16, 1987, Radisson Hotel, Burlington, Vermont / co-sponsored by the Association of Ground Water Scientists and Engineers ... [et al.].
Nitrogen in crop production : proceedings, symposium, 25-27 May, 1982, Sheffield, Alabama / spon. by National Fertilizer Development Center of Tennessee Valley Authority ... [et al.] ; Roland D. Hauck, editor-in-chief.