Portable air supply unit

Chicago citation style
Portable air supply unit. 1980. Retrieved from the Digital Public Library of America, http://ark.digitalcommonwealth.org/ark:/50959/zk51zv16p. (Accessed July 18, 2018.)
APA citation style
(1980) Portable air supply unit. Retrieved from the Digital Public Library of America, http://ark.digitalcommonwealth.org/ark:/50959/zk51zv16p
MLA citation style
Retrieved from the Digital Public Library of America <http://ark.digitalcommonwealth.org/ark:/50959/zk51zv16p>.
Note: These citations are programmatically generated and may be incomplete.