Calder, R. (1951). Profile of science. Allen and Unwin.
Lua i Stíl Chicago (17ú heag.)Calder, Ritchie. Profile of Science. London: Allen and Unwin, 1951.
Lua MLA (8ú heag.)Calder, Ritchie. Profile of Science. Allen and Unwin, 1951.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.