Sheldon X.-C. Lou ... [et al.].Bibliography: p. 23-24.Supported in part by the Air Force Office of Scientific Research under grant AFOSR-82-0258 Supported in part by the Army Research Office under grant DAAG-29-84-K-005 Supported by a Science Scholar Fellowship from the Mary Ingraham Bunting Institute of Radcliffe College, under a grant from the Office of Naval Research.