Helms, R. N. (1980). Illumination engineering for energy efficient luminous environments / (by) Ronald N. Helms. Prentice-Hall.
Chicago Style (17th ed.) CitationHelms, Ronald N. Illumination Engineering for Energy Efficient Luminous Environments / (by) Ronald N. Helms. Englewood Cliffs ; London (etc.): Prentice-Hall, 1980.
MLA (9th ed.) CitationHelms, 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.