Kapp, R. O. (1960). Towards a unified cosmology. Hutchinson.
Cita Chicago (17th ed.)Kapp, Reginald O. Towards a Unified Cosmology. London: Hutchinson, 1960.
Cita MLA (8th ed.)Kapp, Reginald O. Towards a Unified Cosmology. Hutchinson, 1960.
Atenció: Aquestes cites poden no estar 100% correctes.