Bartlett, D. (1994). The direct option. Texas A & M University Press.
Cita Chicago Style (17a ed.)Bartlett, Dick. The Direct Option. College Station: Texas A & M University Press, 1994.
Cita MLA (8a ed.)Bartlett, Dick. The Direct Option. Texas A & M University Press, 1994.
Attenzione: Queste citazioni potrebbero non essere precise al 100%.