Master tables for electromagnetic depth sounding interpretation: R.K. Verma, 1980. Plenum, New York, N.Y., 473 pp., US $ 75.00. After a short discussion (27 pp.) of the theory and interpretation of EM sounding, the rest of the book is occupied by a computer output of numerical tables of mutual coupling ratios for horizontal co-planar, perpendicular, and vertical co-planar loop configurations on the surface of a four- and three-layer earth