1. Carnap, R. (1950). Empiricism, semantics and ontology. Revue Intérnationale de Philosophie, 4, 20–40.
2. Carnap, R. (1963). Replies and systematic expositions. In P. Schilpp (Ed.), The philosophy of Rudolf Carnap (pp. 859–1013). Open Court.
3. Carnap, R. (1966). Philosophical foundations of physics. Basic Books.
4. Carnap, R. (1974). An introduction to the philosophy of science. Dover Publications.
5. Copernicus, Nicolaus. ([1543] 1992). On the revolutions (Translation and Commentary by Edward Rosen). The Johns Hopkins University Press, 1992.