Elonka, S. M. (1973). Standard boiler operators' questions and answers. Tata Mc Graw - Hill.
Chicago Style aipamenaElonka, Stephen Michael. Standard Boiler Operators' Questions and Answers. Mumbai: Tata Mc Graw - Hill, 1973.
MLA aipamenaElonka, Stephen Michael. Standard Boiler Operators' Questions and Answers. Tata Mc Graw - Hill, 1973.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.