Rössler, Otto E. “Ein systemtheoretisches modell zur biogenese/a system theoretic model of biogenesis.” Zeitschrift für Naturforschung B 26, no. 8 (1971): 741-746.
Three types of abstract chemical reaction systems are described: 1. The generalized catalytical system, 2. the generalized autocatalytical system, 3. a spontaneously evolving chemical system. The significance of the second and third system for a very early phase of pre-biological evolution is discussed.