WASET
    Danni Cong and  Meiping Wu and  Hua Mu and  Xiaofeng He and  Junxiang Lian and  Juliang Cao and  Shaokun Cai and  Hao Qin,  Mathematical Modeling of the Working Principle of Gravity Gradient Instrument.   journal   = {International Journal of Geological and Environmental Engineering}, [online]. World Academy of Science, Engineering and Technology.
    July 2017, vol. 129(9). 823 - 827
    [viewed 19 April 2024]. Available from: https://publications.waset.org/pdf/10007891.