1. Bar-Sever YE (1996) A new model for GPS yaw-attitude. JoG 70:714–723
2. Beutler G, Brockmann E, Gurtner W, Hugentobler U, Mervart L, Rothacher M, Verdun A (1994) Extended orbit modeling technique at CODE processing center of the international GPS service for geodynamics (IGS): theory and initial results. Manuscr Geod 19:367–386
3. Dow JM, Neilan RE, Gendt G (2005) The International GPS Service (IGS): celebrating the 10th Anniversary and looking to the next decade. Adv Space Res 36(3):320–326. doi:10.1016/j.asr.2005.05.125
4. Héroux P, Kouba J (2001) GPS precise point positioning with IGS orbit products. Phys Chem Earth A 26:573–578
5. IGS Mail # 591: http://igscb.jpl.nasa.gov/mail/igsmail/1994/msg00166.html