Johnsson, H. (1990). Professional communications for a change. Prentice-Hall.
Chicago Style aipamenaJohnsson, Hans. Professional Communications for a Change. New York: Prentice-Hall, 1990.
MLA aipamenaJohnsson, Hans. Professional Communications for a Change. Prentice-Hall, 1990.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.