APA

Hill L., . (1980). Elementary steps to understanding. Tokio, Japón: Oxford University Press.

Chicago

Hill L.A, . 1980. Elementary steps to understanding. Tokio, Japón: Oxford University Press.

Harvard

Hill L., . (1980). Elementary steps to understanding. Tokio, Japón: Oxford University Press.

MLA

Hill L.A, . Elementary steps to understanding. Tokio, Japón: Oxford University Press. 1980.