Time as it could be measured in artificial living systems. - Andrei D. Robu; Christoph Salge; Chrystopher L. Nehaniv; Daniel Polani (ECAL, 2017)

Measuring Time with Minimal Clocks. - Andrei D. Robu; Christoph Salge; Chrystopher L. Nehaniv; Daniel Polani (Artif. Life, 2019)