On energies of non-extended P-sum of cyclic graphs Rongbing Huang, Sarfraz Ahmad, Muhammad Kamran Siddiqui, Iqra Farman and Yousaf Habib Eur. Phys. J. Plus, 137 2 (2022) 237 Published online: 17 February 2022 DOI: 10.1140/epjp/s13360-022-02449-5