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Ha! I just happened to search for The Presbyterian Philosopher: The Authorized Biography of Gordon H. Clark, by Douglas J. Douma, and what do I find? It is now available on Vyrso! Don't know when it became available but for $7.49 how can one say no? Thank you, FaithLife!
https://vyrso.com/product/136610/the-presbyterian-philosopher-the-authorized-biography-of-gordon-h-clark
