Cattell, R. A. Natural Gas Manual for the Home. Washington D.C.. UNT Digital Library. http://digital.library.unt.edu/ark:/67531/metadc66394/. Accessed May 30, 2015.
Note: Inconsistencies in capitalization and punctuation within the Digital Library may affect this citation. Before using this citation in formal writing, please consult your preferred style manual. More information.