Arto Salomaa. On many-valued systems of logic. Ajatus, vol. 22 (1959), pp. 115–159. - Arto Salomaa. On the composition of functions of several variables ranging over a finite set. Annales Universitatis Turkuensis, Series A, Turun Yliopisto, Turku1960, 48 pp.
A. R. Turquette · Journal of Symbolic Logic · 1960
Arto Salomaa. On many-valued systems of logic. Ajatus, vol. 22 (1959), pp. 115–159. - Arto Salomaa. On the composition of functions of several variables ranging over a finite set. Annales Universitatis Turkuensis, Series A, Turun Yliopisto, Turku1960, 48 pp. - Volume 25 Issue 3