Grey Literature

The search strategy and results contained within a study must be reproduceable, as with any other evidence in a study. 

For further details on how to document a search process please refer to the Cochrane Training Handbook, Chapter 4:

• Identify and record the sources you will search. The sources you search will be informed by your research question and where you expect to find information related to your question.
• Document where you are searching and your search strategies, including document resource name, URL, search terms, and date searched.
• Collect citation information as you go.
• Adhere to your established inclusion and exclusion criteria when selecting sources.

Source: https://guides.library.cornell.edu/evidence-synthesis/grey-literature