Scullin, C. M. (1983). Excavation and grading code administration, inspection and enfocement. Prentice-Hall of India.
Dyfyniad Arddull ChicagoScullin, C Michael. Excavation and Grading Code Administration, Inspection and Enfocement. New Jersey: Prentice-Hall of India, 1983.
Dyfyniad MLAScullin, C Michael. Excavation and Grading Code Administration, Inspection and Enfocement. Prentice-Hall of India, 1983.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.