We translate the classical propositional calculus (CPC) and the intuitionistic propositional calculus (IPC) into the assertive part of $\scr {L}^ {P}$ and show that this translation allows us to ...

Czesław Lejewski, A Propositional Calculus in Which Three Mutually Undefinable Functors Are Used as Primitive Terms, Studia Logica: An International Journal for Symbolic Logic, T. 22 (1968), pp. 17-50 ...