Cady, M. E. (1929). Principles of true science. College Press.
Chicago-čujuhus (17. p.)Cady, Marion E. Principles of True Science. College Press, 1929.
MLA-čujuhus (9. p.)Cady, Marion E. Principles of True Science. College Press, 1929.
Muitte dárkkistit čujuhemiid riektatvuođa, ovdal go geavahat daid iežat deavsttas.