Kenneth G. Wilson (1923). The Columbia Guide to Standard American English. 1993.
Xerox (n.), xerox (n., v.)
Xerox is the trade name of a company and of the copying machines it makes that use xerography to make copies. The lowercase noun and verb are, respectively, a xerographic copy, as in Get me a xerox of this letter, please, and the act of copying with such a machine, as in Please xerox this document for me. Edited English usually prefers the more generic terms (photo)copy, (photo)copying machine, (photo)copier, and (photo)copy. See TRADE NAMES.