Robert WredeRobert Wrede received his B.S. and M.A. degrees from Miami University, Oxford, Ohio. After teaching there for a year, he attended Indiana University and was awarded a Ph.D. in mathematics. He taught at San Jose State University from 1955 to 194. He also consulted at IBM, the Naval Radiation Laboratory at Hunter's Point, and with several textbook companies. His primary interests have been in tensor analysis and relativity theory. The late Murray R. Spiegel received the M.S. degree in Physics and the Ph.D. in Mathematics from Cornell University. He had positions at Harvard University, Columbia University, Oak Ridge, and Rensselaer Polytechnic Institute, and served as a mathematical consultant at several large companies. His last position was as a professor and chairman of Mathematics at the Rensselaer Polytechnic Institute, Hartford Graduate Center. He was interested in most branches of mathematics, especially those which involve applications to physics and engineering problems. He was the author of numerous journal articles and 14 books on various topics in mathematics. Read More Read Less