1. Eadie, T. (1979),Stratified Earth Interpretation Using Standard Horizontal-Loop Electromagnetic Data, University of Toronto, Research in Applied Geophysics,9, p. 37.
2. Koenigsberger, J. G. (1939),Electrische Vertikal-Sondierung von der Erdoberfl�che aus mit der Zentral-Induktions Methode, Beitr. angew. Geophys.7, 112?161.
3. Palacky, G. J., Ritsema, I. L., andDe Jong, S. J. (1981),Electromagnetic Prospecting for Groundwater in Precambrian Terrains in the Republic of Upper Volta, Geophys. Prospect.29, 932?955.
4. Patra, H. P. (1967),Some Studies on Geoelectric Sounding in Engineering and Hydrogeological Problems, Ph.D. Thesis (unpublished), Indian Institute of Technology, Kharagpur.
5. Patra, H. P. (1970),Central Frequency Sounding in Shallow Engineering and Hydrogeological Problems, Geophys. Prospect.18 (2), 236?254.