The main problems of philosophy;
an introduction to philosophy,
by Oswaldo Robles. Translation from the Spanish and introduction by Kurt F. Reinhardt.
APA Citation
Robles, O., Reinhardt, K. F. (Kurt Frank). (1946). The main problems of philosophy: an introduction to philosophy. Milwaukee: The Bruce publishing company.
MLA Citation
Robles, Oswaldo, 1904-, and Kurt F. (Kurt Frank) Reinhardt. The Main Problems of Philosophy: an Introduction to Philosophy. Milwaukee: The Bruce publishing company, 1946.
Warning: These citations may not always be complete (especially for serials).