Portland Cement Association, C. (1964). Handbook of concrete culvert pipe hydraulics. Chicago: Portland Cement Association.
Dyfyniad Arddull ChicagoPortland Cement Association, Chicago. Handbook of Concrete Culvert Pipe Hydraulics. Chicago: Portland Cement Association, 1964.
Dyfyniad MLAPortland Cement Association, Chicago. Handbook of Concrete Culvert Pipe Hydraulics. Chicago: Portland Cement Association, 1964.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.