2008, Catherine Tosenberger, "'Oh my God, the Fanfiction!': Dumbledore's Outing and the Online Harry Potter Fandom", Children's Literature Association Quarterly, Volume 33, Number 2, Summer 2008, page 201:
The day after the release of Deathly Hallows, the community Grindeldore appeared on Livejournal.com. Dedicated to "[f]anworks and discussion on Grindelwald/Dumbledore," the community became a locus for fanfiction, fan art, and fan essays ("meta") on the relationship.
2010, Joel Meredith, "Our Business: Why I'm Glad J. K. Rowling Outed Albus Dumbledore", in Terminus: Collected Papers on Harry Potter, 7-11 August 2008 (ed. Sharon K. Goetz), page 137:
After all, it was immediately after the seventh book release at Prophecy, a fan convention in Toronto, that I first encountered the idea of a "Grindeldore" pairing.
2010, Sigrid Sindhuber, "Slashing Harry Potter: The phenomenon of border-transgression in fan fiction", thesis submitted to the University of Vienna, page 67:
True to her word, slash fans started publishing works including Dumbledore and his childhood friend Grindelwald (also known as Grindeldore) immediately after the release of the last book of the Harry Potter series.
2018, S. P. Sipal, "Did Dumbledore And Grindelwald Make An Unbreakable Vow As Teens?", The Rowling Library Magazine, Issue 21, September 2018, page 24:
The circle on the front poster of the calendar binds Grindeldore together.
