How Do You Find Niche Specific Citation Directories?

Jul 18, 2012
I've been reading up on all the threads in here about the relevancy of citations in 2019. The general consensus seems to be that getting citations in niche directories can be beneficial. My question is this -

What is the best way to find these niche-specific directories? Obviously digging around Google is an option but are there specific search queries you recommend to discover these directories?

Are there are places you go besides Google to uncover these directories?


P.S. I know WhiteSpark offers niche-specific directory submissions so I already have that down as one way to find these sources. I'm looking for other possible ways to find these hidden gems.