Cita APA (7th ed.)

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

Cita Chicago (17th ed.)

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

Cita MLA (9th ed.)

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