Angle random walk error propagation and suppression methods in  long term inertial navigation system
ZHANG Zhong-yi, XU Ye-feng, LI Kui, FENG Pei-de
Journal of Systems Engineering and Electronics . 2011, (9): 2050 -2054 .  DOI: 10.3969/j.issn.1001-506X.2011.09.25