"Satan's Servants" by Robert Bloch. Note: This tale is sometime listed as 'revised' by Lovecraft, as indeed, it was presented here. However, while Lovecraft lent advice on this early tale of Bloch's (which was first written 1935) he does not appear to have written any prose in the story.[1] Lovecraft's notes amounting to a page and half of comments and suggestions are printed here as an appendix.
Chalker, Jack L.; Mark Owings (1998). The Science-Fantasy Publishers: A Bibliographic History, 1923-1998. Westminster, MD and Baltimore: Mirage Press, Ltd. pp. 32–33.
Joshi, S. T. (1999). Sixty Years of Arkham House: A History and Bibliography. Sauk City, WI: Arkham House. pp. 54–55. ISBN0-87054-176-5.
Nielsen, Leon (2004). Arkham House Books: A Collector's Guide. Jefferson, NC and London: McFarland & Company, Inc. pp. 71–72. ISBN0-7864-1785-4.