Another of these dreams he had used as a basis for ‘Pickman’s Model,’ while still another formed the nucleus for ‘The Call of Cthulhu.’ I referred to this story one day, pronouncing the strange word as though it were spelled K-Thool-Hoo. Lovecraft looked blank for an instant, then corrected me firmly, informing me that the word was pronounced, as nearly as I can put it down in print, K-Lütl-Lütl. I was surprised, and asked why he didn’t spell it that way if such was the pronunciation. He replied in all seriousness that the word was originated by the denizens of his story and that he had only recorded their own way of spelling it. Lovecraft’s own invention had assumed an actual reality in his mind.

— Donald Wandrei, “Lovecraft in Providence,” in Peter Cannon, ed., Lovecraft Remembered, 1998