Documents distributed by their authors (individuals or organizational units) but not distributed through official government channels, e.g., Canada Communication Group (CCG), or departmental distribution services. Copies of grey literature are usually distributed in limited numbers.
A term, mainly used by librarians, to describe material that isn't available commercially and hasn't been formally published. An example of grey literature would be an internal report produced for use within an organization.
Unpublished or un-indexed reports. These can include conference proceedings, non-indexed journals, internal reports, pharmaceutical industry reports and student dissertations and theses.