When I'm trying to track down who’s most popular among lesser-known authors, my usual tactic is a tiny bit of detective work and a lot of patience. I dug through everything I could think of and, honestly, there isn't a clear, widely recognized novel credited as Graham Montague's 'most popular' in the usual public sources. That can mean a few things: he might be a niche or local author, a pen name, or someone who has done most of their publishing through small presses or self-publishing channels where mainstream charts don’t always reflect popularity.
If you want to be thorough, start with a few practical checks that I use whenever I hunt down this kind of info. Look for an author page on major book hubs and sort by ratings and reviews to see which title pops up most often; Amazon's author page and best-seller ranks can show which title sells better; WorldCat or your national library catalog will reveal which books libraries have ordered (a decent proxy for broader recognition); and Google Books or publisher sites sometimes list sales or translations. For indie authors, Kindle store rankings, item counts on Goodreads (number of ratings and reviews), and even social media presence (bookstagram, booktok, Twitter threads) often give a clearer picture than mainstream media coverage.
I’ve ended up finding the right title before just by following a single Goodreads user who loved a tiny-press novel — personal recommendations can lead to surprisingly accurate measures of ‘popularity’ within a community. If you can share a little more (cover art, publisher name, a snippet of the blurb), I’d happily dig deeper for you. Otherwise, posting a short query with a screenshot on a reading forum or a Facebook author group often yields fast results from folks who already follow niche writers. I kind of love these little hunts — they’re like following a trail of bookmarks and fan notes — and I’d be curious to see what we turn up together.