Dyfyniad APA

Langley, B. C. (1990). Heating, ventilating, air conditioning, and refrigeration (4th ed.). Prentice-Hall.

Dyfyniad Arddull Chicago

Langley, Billy C. Heating, Ventilating, Air Conditioning, and Refrigeration. 4th ed. Englewood Cliffs, N.J: Prentice-Hall, 1990.

Dyfyniad MLA

Langley, Billy C. Heating, Ventilating, Air Conditioning, and Refrigeration. 4th ed. Prentice-Hall, 1990.

Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.