Cita APA (7a ed.)

Helweg, H. (1978). The Old Woman and her Pig. Oxford University Press.

Cita Chicago Style (17a ed.)

Helweg, Hans. The Old Woman and Her Pig. Oxford: Oxford University Press, 1978.

Cita MLA (9a ed.)

Helweg, Hans. The Old Woman and Her Pig. Oxford University Press, 1978.

Precaución: Estas citas no son 100% exactas.