Elgerd, O. I. (1971). Electric energy systems theory: An introduction. New York: McGraw-Hill.
Dyfyniad Arddull ChicagoElgerd, Olle I. Electric Energy Systems Theory: An Introduction. New York: McGraw-Hill, 1971.
Dyfyniad MLAElgerd, Olle I. Electric Energy Systems Theory: An Introduction. New York: McGraw-Hill, 1971.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.