S. Team, “Non-differentiable Delay-interval-dependent Exponentially Passive Conditions for Certain Neutral Integro-differential Equations with Time-varying Delays: Watcharin Chartbupapan, Thongchai Botmart, Kanit Mukdasai, Narongrit Kaewbanjak”, Thai J Math, vol. 18, no. 1, pp. 233–251, Mar. 2020.