John Conrad Jaeger received a first-class honours degree in mathematics and physics from the University of Sydney, was Wrangler (class I) in the Mathematical Tripos at Cambridge, and received a DSc in applied mathematics from the University of Sydney. He was a professor at the University of Tasmania and the Australian National University. He was the author of several monographs in applied mathematics, including, with H. S. Carslaw, Conduction of Heat in Solids, and was a Fellow of the Australian Academy of Science and the Royal Society.

Neville G. W. Cook received a BS and PhD in geophysics from the University of Witwatersrand. He was the founder and first director of the Mining Research Laboratory of the South African Chamber of Mines, and in 1971 he received the Gold Medal of the Scientific and Technical Societies, the highest scientific award in South Africa. He was Donald H. McLaughlin Chair in Mineral Engineering at the University of California at Berkeley, and was a member of the U. S. National Academy of Engineering.

Robert Zimmerman received BS and MS degrees from Columbia University, and a PhD from the University of California at Berkeley. He has been a staff scientist in the Earth Sciences Division of the Lawrence Berkeley National Laboratory, and Reader in Rock Mechanics at Imperial College, London. He is currently Professor of Engineering Geology at the Royal Institute of Technology in Stockholm, and co-editor of the International Journal of Rock Mechanics. He is also the author of the monograph Compressibility of Sandstones.