作者：Zumberge, J. F., and W. I. Bettiger,
标题：Ephemeris and Clock Navigation Message Accuracy, in Global Positioning System - Theory and Applications, vol. I, edited by B. W. Parkinson and J. J. Spilker, 585-599,
来源：Am. Inst. of Aeronautics and Astronautics, Inc., Washington, D.C., 1996.