Polar Bears. Ian Stirling, with photographs by Dan Guravich.

Whales, Dolphinsand Porpoises. Consulting Editors Sir Richard Harrison and Dr. M. M. Bryden.

Biologyand Conservationofthe River Dolphins. W. F. Perrin, R. L. Brownell, Jr., Z. Kaiya and L. Jiankang (eds.).

Animal Sonar. Processesand Performance. P. E. Nachtigall and P. W. B. Moore (eds.).

North Atlantic Killer Whales. J. Sigurjonsson and S. Leatherwood (eds.).