A class of isochronous and non-isochronous nonlinear oscillators J. Ramya Parkavi, R. Mohanasubha, V. K. Chandrasekar, M. Senthilvelan and M. Lakshmanan Eur. Phys. J. Spec. Top., 231 11-12 (2022) 2387-2399 Published online: 05 March 2022 DOI: 10.1140/epjs/s11734-022-00484-y