Abler , R., & Alber, R. .. ,. (1975). Human geography in a shrinking world: By Ronald Abler , Donald Janelle , Allen Philbrick and John Sommer. Duxbury.
Citazione stile Chigago Style (17a edizione)Abler , Ronald, e Ronald . ,,, Alber. Human Geography in a Shrinking World: By Ronald Abler , Donald Janelle , Allen Philbrick and John Sommer. Massachusetts: Duxbury, 1975.
Citatione MLA (9a ed.)Abler , Ronald, e Ronald . ,,, Alber. Human Geography in a Shrinking World: By Ronald Abler , Donald Janelle , Allen Philbrick and John Sommer. Duxbury, 1975.
Attenzione: Queste citazioni potrebbero non essere precise al 100%.