Cita APA (7a ed.)

Sheppard, G., & Vaughan, T. W. (1937). The geology of south-western Ecuador. London : T. Murby & co..

Cita Chicago Style (17a ed.)

Sheppard, George, y Thomas Wayland Vaughan. The Geology of South-western Ecuador. London : T. Murby & co., 1937.

Cita MLA (8a ed.)

Sheppard, George, y Thomas Wayland Vaughan. The Geology of South-western Ecuador. London : T. Murby & co., 1937.

Cita IICA/CATIE

Sheppard, G., ; Vaughan, T. W. 1937. The geology of south-western Ecuador. London : T. Murby & co..