A new hidden attractor hyperchaotic memristor oscillator with a line of equilibria Yu Feng, Karthikeyan Rajagopal, Abdul Jalil M. Khalaf, Fawaz E. Alsaadi, Fuad E. Alsaadi and Viet-Thanh Pham Eur. Phys. J. Special Topics, 229 6-7 (2020) 1279-1288 Published online: 26 March 2020 DOI: 10.1140/epjst/e2020-900097-0