APA

Graebner N., . (1961). An uncertain tradition. Estados Unidos: McGraw-Hill Book Company.

Chicago

Graebner Norman, . 1961. An uncertain tradition. Estados Unidos: McGraw-Hill Book Company.

Harvard

Graebner N., . (1961). An uncertain tradition. Estados Unidos: McGraw-Hill Book Company.

MLA

Graebner Norman, . An uncertain tradition. Estados Unidos: McGraw-Hill Book Company. 1961.