Ross, R. S. (1977). Speech communication: Fundamentals and practice (4th ed.). Prentice-Hall.
Dyfyniad Arddull ChicagoRoss, Raymond S. Speech Communication: Fundamentals and Practice. 4th ed. Englewood Cliffs: Prentice-Hall, 1977.
Dyfyniad MLARoss, Raymond S. Speech Communication: Fundamentals and Practice. 4th ed. Prentice-Hall, 1977.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.