Complete group classification of systems of two linear second-order ordinary differential equations. - Sibusiso Moyo; Sergey V. Meleshko; G. F. Oguis (Commun. Nonlinear Sci. Numer. Simul., 2013)

Complete group classification of systems of two nonlinear second-Order ordinary differential equations of the form y′′=F(y). - G. F. Oguis; Sibusiso Moyo; Sergey V. Meleshko (Commun. Nonlinear Sci. Numer. Simul., 2017)