Ray. Walden X 40. Indiana University Press.
Chicago Style (17th ed.) ZitazioaRay. Walden X 40. Indiana University Press.
MLA (9th ed.) ZitazioaRay. Walden X 40. Indiana University Press.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.
Ray. Walden X 40. Indiana University Press.
Chicago Style (17th ed.) ZitazioaRay. Walden X 40. Indiana University Press.
MLA (9th ed.) ZitazioaRay. Walden X 40. Indiana University Press.