Tipper, H. (1976). Controlling overhead. Taraporevala publishing.
Dyfyniad Arddull ChicagoTipper, Harry. Controlling Overhead. Bombay: Taraporevala publishing, 1976.
Dyfyniad MLATipper, Harry. Controlling Overhead. Taraporevala publishing, 1976.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.