C. Jeevarathinam, S. Rajasekar, and M. Sanjuán, “Vibrational Resonance in the Duffing Oscillator with Distributed Time-Delayed Feedback”, JAND, vol. 4, no. 4, pp. 391–404, Nov. 2015, doi: 10.5890/JAND.2015.11.006.