Finding so-called “grey literature” — material from publications not produced by commercial publishers — has always been a challenge for researchers. The most valuable grey literature is often not easily retrieved through a simple query in a search engine; it resides inside a specialized database, buried deep within an association’s web site, or is simply not ranked as relevant by a search engine’s algorithm.

The problem of finding grey literature is not new; research on and discussion about grey lit in the STM field has been going on for years (see, for example, the International Conference on Grey Literature, which has been meeting since 1993). More recently, business researchers are finding that sometimes non-traditional resources have the best — or only — information on a narrow topic or current issue. Following are some of the tricks I use for finding hidden or grey-lit business resources.

Think like a detective. Look for clues and pointers to the next resource rather than hoping to find the exact information you want. Keep your eyes open for unexpected sources and be prepared to spend more time than you’re probably accustomed to, wading through results to find the hidden nugget.

Start with a libguide. I have often been surprised to find well-sourced libguides on topics I thought too narrow for any library to have developed a finding tool for. A search approach that often works is simply to add inurl:libguides to your search query.

Look for more of the good stuff. Once you find one good source, search for other mentions of that source, on the assumption that other sources will be mentioned as well. For example, if you find that the United Nations’ FAOSTAT web site (www.fao.org/faostat/) is useful, try running a phrase search for “fao.org/faostat/” to find other food and agricultural resources.

Use Google Scholar as well as Google or your search engine of choice; there is very little overlap and Google Scholar contains more than scholarly articles.

Use words that are likely to be used to describe what you’re looking for, such as (“technical report” OR “conference proceedings” OR “white paper”) or (“institutional repository” OR “open access repository”). Limit your search to the most likely file formats with (filetype:pdf OR filetype:doc OR filetype:docx).

Consider using the Millionshort.com search engine, which allows you to eliminate the top million most popular web pages from your search results. This lets you find more obscure pages from small organizations that might never get surfaced in a general search engine query.

And remember that the professional online services often include selected grey literature. Find the appropriate filter in the service you subscribe to; it’s usually called something like Document Type or Source Category. As with the “look for more of the good stuff” approach above, try a search with broad keywords and limited to the document types that indicate grey literature, such as Think Tanks, Conference Papers, Working Papers and so on.

I recently wrote a column for Online Searcher on what I call “bonsai research” — research in narrowly focused markets in which there isn’t likely to be much information, with some additional thoughts on how to find that elusive grey business literature.