Cita APA (7a ed.)

Harper, S. (1987). A humanistic approach to the study of rural populations. [s.n.].

Cita Chicago Style (17a ed.)

Harper, Sarah. A Humanistic Approach to the Study of Rural Populations. [S.l.]: [s.n.], 1987.

Cita MLA (9a ed.)

Harper, Sarah. A Humanistic Approach to the Study of Rural Populations. [s.n.], 1987.