Cita APA (7th ed.)
Elonka, S. M., & Kohan, A. L. (1969). Standard boiler operators' questions and answers. McGraw-Hill.
Cita Chicago (17th ed.)
Elonka, Stephen Michael, i Anthony Lawrence Kohan. Standard Boiler Operators' Questions and Answers. New York ; New delhi: McGraw-Hill, 1969.
Cita MLA (9th ed.)
Elonka, Stephen Michael, i Anthony Lawrence Kohan. Standard Boiler Operators' Questions and Answers. McGraw-Hill, 1969.
Atenció: Aquestes cites poden no estar 100% correctes.