"Dan Harmon" refers to at least two distinct authors and perhaps a third. One Dan Harmon founded Channel 101 and co- wrote the "Scud the Disposable Assassin" series, another Dan Harmon wrote the books on Christianity, and yet another Dan Harmon may have written about psychological disorders.
Unfortunately, LT can not at this time make a distinction between authors with the same name.
2. Harmon, Dan, 1973-
3. Harmon, Daniel E.