Grey literature is difficult to define, but its main characteristics are that its production and distribution is outside the realm of commercial publishing, and that it is ephemeral (Schopfel, J. & Farace, D.J. 'Grey literature' in Encyclopedia of Library and Information Science, 3rd ed. DOI: 10.1081/E-ELIS3-120043732).
Grey literature "may include, but are not limited to the following types of materials: reports (pre-prints, preliminary progress and advanced reports, technical reports, statistical reports, memoranda, state-of-the art reports, market research reports, etc.), theses, conference proceedings, technical specifications and standards, non-commercial translations, bibliographies, technical and commercial documentation, and official documents not published commercially (primarily government reports and documents)."
Image source: Fade Library Early Morning by Kieran Lamb (CC BY-SA 2.0)
Gender and sexuality studies 'depends on access to to archival collections, pamphlet material, unpublished scholarship, and grass-roots or small press publications' (Greening, A. 'Archival materials' in Information sources in women's studies and feminism, Olson, H.A. ed., Munchen: K.G. Sauer, 2010).
Searching the grey literature offers the potential to balance any tendencies for publication bias (PHCRIS http://www.phcris.org.au/guides/grey_literature.php. Accessed 9 Nov 15). In gender and sexuality studies, publication bias is the tendency for the voices of certain groups to have been excluded from mainstream publication during certain periods due to gender, sexual identity, race or social status. This exclusion means that it is sometimes necessary to go to grey literature to find these excluded voices.
Key questions to ask include:
Google and Google Scholar can be good sources for finding grey literature. To avoid unwanted results, use operators to limit your search.
Google Operators To search Google by domain or site, use
Google Advanced (Found under Settings in bottom right corner) Provides rudimentary search fields as well as limiters including region, site/domain, file type or where the search terms appear on the page. Google Scholar uses similar search strategies but with results limited to academic resources.
As with all information, it is important to identify whether the information contained in grey literature is credible. Be aware of private research organisations, 'think tanks' etc as they have their own commercial, political or social interests and biases.
The AACODS Checklist, (Authority, Accuracy, Coverage, Objectivity, Date, Significance) by Jess Tyndal at Flinders University, is a good resource on evaluating grey literature.
(Content courtesy of La Trobe Univerity Library)