Blum, L. A. (1980). Friendship, altruism and morality. Routledge.
Chicago-čujuhus (17. p.)Blum, Lawrence A. Friendship, Altruism and Morality. London: Routledge, 1980.
MLA-čujuhus (9. p.)Blum, Lawrence A. Friendship, Altruism and Morality. Routledge, 1980.
Muitte dárkkistit čujuhemiid riektatvuođa, ovdal go geavahat daid iežat deavsttas.