As the scope of grey literature is extremely broad, Franklin Sayre (Introduction to the Grey Literature for the Health Sciences, slide no.8, February, 2014) recommends considering the following questions in order to narrow down your search:
Source Guide: USC and Whichita (see links and license below)
The resources below provide detailed guidance on how to approach searching grey literature.
We gratefully acknowledge that the content of this guide (including links, descriptions, and selected categories) is reused/remixed from the following guides and sources under a Creative Commons Attribution NonCommerical ShareAlike 4.0 International License.
Confirmation of the Creative Commons status of the entire USC guide was also sought and received in writing from the USC Guide Author Karin Saric on 11 July 2019. Reuse permission was granted provided attribution is given.