George Allen & Unwin Ltd. (1994). How things work: The universal encyclopedia of Machines Vol. II. Harper Collins Publications.
Chicago Style aipamenaGeorge Allen & Unwin Ltd. How Things Work: The Universal Encyclopedia of Machines Vol. II. New delhi: Harper Collins Publications, 1994.
MLA aipamenaGeorge Allen & Unwin Ltd. How Things Work: The Universal Encyclopedia of Machines Vol. II. Harper Collins Publications, 1994.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.