Nth-order smooth positon and breather-positon solutions of a generalized nonlinear Schrödinger equationN. Vishnu Priya, S. Monisha, M. Senthilvelan and Govindan RangarajanEur. Phys. J. Plus, 137 5 (2022) 646DOI: https://doi.org/10.1140/epjp/s13360-022-02861-x