Dyfyniad APA
Johnson, H. (1990). Professional communications - for a change. Prentice Hall.
Dyfyniad Arddull Chicago
Johnson, Hans. Professional Communications - for a Change. New york: Prentice Hall, 1990.
Dyfyniad MLA
Johnson, Hans. Professional Communications - for a Change. Prentice Hall, 1990.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.