Cita APA (7a ed.)

Fagan, M. (1991). Challenge for change: [geographical approaches to selected world issues] (2. ed.). McGraw-Hill.

Cita Chicago Style (17a ed.)

Fagan, Margaret. Challenge for Change: [geographical Approaches to Selected World Issues]. 2. ed. Toronto [u.a.]: McGraw-Hill, 1991.

Cita MLA (9a ed.)

Fagan, Margaret. Challenge for Change: [geographical Approaches to Selected World Issues]. 2. ed. McGraw-Hill, 1991.