Gaya APA

Ikoku, C, U. (1980). Natural gas engineering. A systems approach (Fotocopy) (1980). : Oklohama : PennWell Publishing Company,.

Gaya MLA

Ikoku, Chi, U. "Natural gas engineering. A systems approach (Fotocopy)". 1980 : Oklohama : PennWell Publishing Company,, 1980. Text.