"Lógica simbólica y matemática." . . "Inductie (logica)" . . "Inductief-deductief redeneren." . . "Logic, Symbolic and mathematical." . . "Hipótesis del continuo." . . . . "The continuum of inductive Methods" . . . . . "The continuum of inductive methods"@en . "The continuum of inductive methods" . . . . . . . . . . . . . "The Continuum of Inductive Methods"@en . . . . . . . . . . . . . . . . . . . . . . . . . "Lógica simbólica matemática." . . "Induction (Logic)" . . "Logique symbolique et mathématique." . .