Sinha, Nirbhay Kumar. “First Order Normalization in the Generalized Photo Gravitational Non-Planar Restricted Three Body Problems”. International Journal of Advanced Astronomy 3, no. 2 (June 13, 2015): 46–52. Accessed November 21, 2024. https://sciencepubco.com/index.php/IJAA/article/view/4652.