Pascual-Leone, Juan. “Affirmations and Denials, Perturbations and Contradictions, in Piaget: Is His Latest Theory Causal?”. Tarbiya, revista de Investigación e Innovación Educativa, no. 5 (November 1, 1993): 31–38. Accessed September 10, 2025. https://revistas-new.uam.es/tarbiya/article/view/18023.