Another group test:

JURN group test: “Alan Moore” Watchmen
May 2014. Searching for free full-text scholarly articles, theses or book chapters in English, with primary discussion of the famous and seminal graphic novel Watchmen by Alan Moore. Not counting film criticism of the movie version, or book reviews. Clicked through on possible results, and briefly evaluated.
DOAJ 0 Used ‘Article’ search. 0 from four results.
Journal Click 0 0 from zero results. Seems to include a lot of predatory titles and publishers.
JournalTOCS 0 0 from zero results.
Ingenta Connect 0 0 from six paywalled results.
Journal Seek 0 0 from zero results.
Mendeley 0 Searched ‘Articles’ only, then filtered for Open Access articles only — which produced no relevant results. Then removed the OA filter, which gave three relevant results — that were found to be paywalled.
OAlib 0 From 16 results. Had a couple of relevant articles but these were not in English.
Google Search 0 Forced verbatim. Examined first 50 results. As you’d expect, a mess of commercial book listings pages and the occasional pop-cult interview with Moore. The addition of filetype:pdf helped — giving a scattering of student dissertations; the 1st (but not 2nd) edition of the Annotated Watchmen document; and a short undergraduate attempt at a bibliography of scholarly works on Watchmen.
Microsoft Academic 1 One of four results.
CORE 2 Filtered search by English language. CORE offered many incidental or spurious results.
OATD 3 Three from 14 results.
Digital Commons Network 3 Three from 17 results.
NDLtd 3 Three from 12 results.
Google Scholar 8 Examined first 50 results. Google Books links not counted. Five of the good results were from the open journal ImageTexT: interdisciplinary comics studies. Two likely good candidates proved to be “404 Not Found”.
BASE 9 Searched ‘Verbatim’ on ‘Entire Document’. Examined first 50 results.
OPENDoar 12   Examined first 50 results. Two appeared to be basic undergraduate seminar papers.
JURN 25   Checked first 50 results, not counting interviews, book reviews and duplicates. Results remained strong and on-topic right through to result 100.

For JURN, adding an additional search modifier helps to nudge away incidental and duplicate results…

   “Alan Moore” intitle:Watchmen
   [force intitle:]

   “Alan Moore” Watchmen Rorschach
   [add focus by adding the name of a key character]

   “Alan Moore” Watchmen
   [remove duplicates]