Unsaturated soil engineering practice : committee report by the Subcommittee on Unsaturated Soils (Committee on Soil Properties) and the Committee on Shallow Foundations of the Geo-Institute, in cooperation with the ISSMFE TC6 Committee on Unsaturated Soils: also the proceedings of sessions on unsaturated soils at Geo-Logan '97 sponsored by the Geo-Institute of the American Society of Civil Engineers, Logan, Utah, July 15-19, 1997 - Houston, Sandra L.; Fredlund, D. G. (Geotechnical special publication, 1997)