Erle C. Donaldson is an independent consultant and managing editor of the Journal of Petroleum Science and Engineering. He was elected to the International Hall of Fame for Science in 1993. He has received a distinguished service award from the Republic of Honduras and other honors from the U.S. Department of Energy, the National Petroleum Engineering Honor Society, and the University of Oklahoma. Dr. Donaldson has written, co-authored, and served as editor on numerous articles and books.Djebbar Tiab is Professor Emeritus at the University of Oklahoma, where he served as Professor of petroleum engineering from 1977 - 2014. His B.Sc., M.Sc. and Ph.D. are in petroleum engineering. He is GM and Owner of UPTEC (United Petroleum Technology LLC), a training and consulting company. He has taught graduate petroleum engineering courses at the African University of Science and Technology since 2008. Before joining the University of Oklahoma, he was a Research Associate and Assistant Professor at the New Mexico Institute of Mining and Technology. Djebbar worked in Algerian oil fields for Alcore S.A. as well as for Core Laboratories and Western Atlas as Senior Reservoir Engineer Advisor. Dr. Tiab has taught courses on reservoir engineering, production, well test analysis and reservoir characterization, and authored/co-authored over 260 technical papers on pressure transient analysis, dynamic flow analysis, petrophysics, natural gas engineering, reservoir characterization, reservoir engineering, and injection processes.