C. C. Chang. Logic with positive and negative truth values. Proceedings of a Colloquium on Modal and Many-valued Logics, Helsinki, 23–26 August, 1962, Acta philosophica Fennica, no. 16, Helsinki1963, pp. 19–39.
Bruno Scarpellini · Journal of Symbolic Logic · 1971
C. C. Chang. Logic with positive and negative truth values. Proceedings of a Colloquium on Modal and Many-valued Logics, Helsinki, 23–26 August, 1962, Acta philosophica Fennica, no. 16, Helsinki1963, pp. 19–39. - Volume 36 Issue 2