Engineering. Charles Robert Johnson.
Dyfyniad Arddull ChicagoEngineering. London: Charles Robert Johnson.
Dyfyniad MLAEngineering. Charles Robert Johnson.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.
Engineering. Charles Robert Johnson.
Dyfyniad Arddull ChicagoEngineering. London: Charles Robert Johnson.
Dyfyniad MLAEngineering. Charles Robert Johnson.