Sable, M. H. (1987). Reference as a Required Subject in the World's Educational Systems.
Citazione stile Chigago Style (17a edizione)Sable, Martin H. Reference as a Required Subject in the World's Educational Systems. 1987.
Citatione MLA (9a ed.)Sable, Martin H. Reference as a Required Subject in the World's Educational Systems. 1987.
Attenzione: Queste citazioni potrebbero non essere precise al 100%.