APA (7th ed.) Citation

Helms, R. N. (1980). Illumination engineering for energy efficient luminous environments / (by) Ronald N. Helms. Prentice-Hall.

Chicago Style (17th ed.) Citation

Helms, Ronald N. Illumination Engineering for Energy Efficient Luminous Environments / (by) Ronald N. Helms. Englewood Cliffs ; London (etc.): Prentice-Hall, 1980.

MLA (9th ed.) Citation

Helms, Ronald N. Illumination Engineering for Energy Efficient Luminous Environments / (by) Ronald N. Helms. Prentice-Hall, 1980.

Warning: These citations may not always be 100% accurate.