"Mendeley searches document details - including the 'General notes' field - as well as within the body text of any PDF papers in your library" (Use search to retrieve references, ¶2< 2016.10.06).
"a wonderful search engine that has been around for over a decade now, providing information to authors who want to learn more about the copyright and open access policies of journals" (Lawson, Ask RoMEO…, ProfHacker blog, 2012.10.16)