APA (7th ed.) Zitazioa

Abler , R., & Alber, R. .. ,. (1975). Human geography in a shrinking world: By Ronald Abler , Donald Janelle , Allen Philbrick and John Sommer. Duxbury.

Chicago Style (17th ed.) Zitazioa

Abler , Ronald, eta Ronald . ,,, Alber. Human Geography in a Shrinking World: By Ronald Abler , Donald Janelle , Allen Philbrick and John Sommer. Massachusetts: Duxbury, 1975.

MLA (9th ed.) Zitazioa

Abler , Ronald, eta Ronald . ,,, Alber. Human Geography in a Shrinking World: By Ronald Abler , Donald Janelle , Allen Philbrick and John Sommer. Duxbury, 1975.