L. I. Niel, “Semantics and ontology: Reflections on the Wissenschaftslehre of Bolzano”, PT, vol. 69, no. 261 S.Esp, pp. 939–962, Jan. 2015, Accessed: Aug. 12, 2026. [Online]. Available: https://revistas.comillas.edu/pensamiento/article/view/4722