is not available in traditional channels of publishing and distribution
is not well represented in indexing sources
Advantages of grey literature
newly disseminated findings
information from unpublished studies
reports and statistics which may not be available in traditional publishing
Established definitions of grey literature
"Information produced on all levels of government, academia, business and industry in electronic and print formats not controlled by commercial publishing i.e. where publishing is not the primary activity of the producing body".
International Conference on Grey Literature Luxembourg definition, 1997. Expanded in New York, 2004.
“Literature which is not readily available through normal book selling channels, and therefore difficult to identify and obtain”.
Auger, C. P. (1989). Information sources in grey literature. London: Bowker-Saur.