5Sheng-Wu Liu,Zhao-nian Zhang,Jamdes C.Hung.A High Accuracy Magnetic Heading System Composed of fluxgate Magnetometers and a Microcomputer[J].IEEE, 1989:CH2759-9/B90000-0148.
6GW.Barber, A.S.Arrott. History and Magnetics of Compass Adusting[J]. IEEE Transctions on magnetics.Vol.24.No.6, November 1988.