Ladd, John, 1917- Ladd, John, 1917- The structure of a moral code : a philosophical analysis of ethical discourse applied to the ethics of the Navaho Indians. - Cambridge : Harvard University Press, 1957. Bibliography: p. [427]-436. LCCN: 56013287 Subjects--Topical Terms: Indian ethics.Navajo Indians.Ethics. LC Class. No.: E98.E83 / L3 Dewey Class. No.: 970.617