Einstein, H.H., Markow, M.J., and Chew, K. (1977). Assessing the value of exploration for underground gas storage caverns. In: Proceedings of the 1^st International Symposium on Storage in Excavated Rock Caverns (Rockstore 77), Stockholm, Sweden, 5–8 September 1977. Also in: International Journal of Rock Mechanics and Mining Sciences & Geomechanics Abstracts, 16 (4), 83. doi:10.1016/0148-9062(79)91268-3