Butt, J., & John Butt. (2000). Spanish verbpack. Oxford,New York: Oxford University Press.
Chicago Style aipamenaButt, John, và John Butt. Spanish Verbpack. Oxford,New York: Oxford University Press, 2000.
MLA aipamenaButt, John, và John Butt. Spanish Verbpack. Oxford,New York: Oxford University Press, 2000.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.