Learning Google search commands can help you find Gray Literature when searching in Google! Below are some particularly useful search commands: 

site

• What it does: Searches within a specific site or domain. Useful for locating information from specific government organizations. Also useful for locating materials more generally from .gov or .edu domains. 
  • Examples: site:who.int or site:.gov
• Notes: Be careful if searching for site:.edu. Not all websites that end in .edu are universities or other educational institutions, the domain can be used by anyone. 

Filetype

• What it does: Searches for specific file types. Useful for looking for reports, white papers, working papers, or factsheets. 
  • Examples: filetype:pdf
• Notes: There may be information you are missing if you limit to one filetype! 

• Additional Examples

  • Example search: Lyme disease site:who.int filetype:pdf
    • What it retrieves: This search retrieves pdf files published to the web on the WHO website. 
  • Example search: bt corn site:usda.gov
    • What it retrieves: This search retrieves any information on bt corn on the USDA website. 

Gray literature is literature that is published, or produced, outside of the traditional scholarly publishing cycle. Gray literature can include: 

• Government reports
• White papers
• Working papers
• Technical notes 
• Patents