Lost HP Lovecraft work commissioned by Houdini escapes shackles of history
theguardian.com
theguardian.com
That book has an entry in Wikipedia even if there's less than 4000 copies of it:
https://en.wikipedia.org/wiki/The_Dark_Brotherhood_and_Other...
The picture in the article, if real, features exactly the title page of the already published chapter.
"The Cancer of Superstition was previously known only in outline and through its first chapter. Houdini had asked Lovecraft in 1926 to ghostwrite the treatise exploring superstition, but the magician’s death later that year halted the project, as his wife did not wish to pursue it."
And it's probably not written by Lovecraft but CM Eddy, as stated near the end of the article, "according to Lovecraft scholar ST Joshi."