Final answer:
Grey literature refers to documents not normally published through academic channels, including reports, papers, theses, and government documents.
Step-by-step explanation:
Grey literature refers to documents that are not formally published through traditional academic channels but are still valuable sources of information. It includes documents issued by governmental agencies, academic institutions, and other groups, such as papers, reports, technical notes, newsletters, working papers, theses, government documents, bulletins, fact sheets, and conference proceedings.
Grey literature is not related to academic research, as it is not peer-reviewed or commonly indexed by commercial publishers.