Gary Walker. (2001). IT Problem Management. Prentice-Hall.
Dyfyniad Arddull ChicagoGary Walker. IT Problem Management. Prentice-Hall, 2001.
Dyfyniad MLAGary Walker. IT Problem Management. Prentice-Hall, 2001.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.