An interesting snippet which I picked up from a post by Fun Guy from Yuggoth on the redoubtable yog-sothoth.com: according to this William Burroughs was taught by Lovecraft's literary executor Robert H. Barlow while studying anthropology in Mexico. Barlow apparently introduced Burroughs to the study of the Mayan Codices.
While I was aware of Barlow's career in anthropology and Burrough's early interest in the subject matter, it never occured to me that the two may have met.
Admittedly Burroughs' connection with things Lovecraftian is somewhat tenuous: outside of the infamous blurb he supplied for the (equally infamous) Simon Necronomicon (though curiously absent from later printings), Burroughs did include cut-ups of parts of Frank Belknap Long's 'The Hounds of Tindalos' in (if I remember aright) The Place of Dead Roads. I'm not aware that Burroughs ever mentioned Lovecraft by name, and I don't recall reading anything about Lovecraft in the Burroughs' biographies I've read. Even so, one wonders if Burroughs first heard of Lovecraft as a result of this meeting?