APA (7e ed.) Bronvermelding

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

Chicago (17e ed.) Bronvermelding

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

MLA (9e ed.) Bronvermelding

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