Grey literature is information that is not typically produced, published or distributed through traditional or commercial publishing channels.
Examples of grey literature include: patents, technical reports, theses and dissertations, conference proceedings, marketing research, working papers, white papers, fact sheets, standards, policy statements, business documents, government documents and pre-prints.
How do I find grey literature?
Grey literature can be extremely narrow in scope and extremely subject specific.
To start, consider what types of organizations might produce the information you are looking for.
For example, consider: government agencies, advocacy groups, non-governmental organizations, industries, trade or professional organizations.
Reference lists and bibliographies of published articles are great resources to use when trying to locate grey literature.
Use the “filetype:pdf” search filter in Google because a lot of grey literature is published in PDF format.
Use the “site:domain” search filter to search within a website or domain. For example: reports site:gc.ca
Why do I need grey literature?
Grey literature provides a comprehensive understanding of a topic.
In some areas of research, the best source for information might be grey literature.
Grey literature can be a great source of raw data, statistics or recent changes in a field.
Because of the lengthy time it takes for traditional peer-reviewed journals and books to publish, research results such as conference proceedings might appear more quickly in grey literature channels. In short, grey literature can be timely.