According to The Twelfth International Conference on Grey Literature (2010), grey literature is the name given to literature that is not widely disseminated, but is of sufficient quality to be housed by repositories or libraries. It is usually distributed by individuals or non-commercial publishers.
Common examples of grey literature include:
A video about grey literature by the Australian National University (2023).
ANU Library. (2023, January 20). What is grey literature? [Video]. YouTube. https://www.youtube.com/watch?v=bQsIwHxDldg
Schopfel, J. (2011). Towards a Prague definition of grey literature. The Grey Journal, 7(1), 5-18. https://archivesic.ccsd.cnrs.fr/sic_00581570/document
Lefebvre, C., Glanville, J., Briscoe, S., Featherstone, R., Littlewood, A., Metzendorf, M.-I., Noel-Storr, A., Paynter, R., Rader, T., Thomas, J., & Wieland, L. S. (2024). Technical supplement to chapter 4: Searching for and selecting studies. In J. P. T. Higgins, J. Thomas, J. Chandler, M. Cumpston, T. Li, M. J. Page, & V. A. Welch (Eds.), Cochrane handbook for systematic reviews of interventions (Version 6.5). Cochrane. https://www.cochrane.org/authors/handbooks-and-manuals/handbook/current/chapter-04-technical-supplement-searching-and-selecting-studies
Grey literature can be produced by a variety of people or organisations. Common producers of grey literature include: