From an interview posted at Outpost Gallifrey (used by permission). 
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There are authors you love who have no influence on your style at all--mostly because (I'm thinking of Nabokov here) they're geniuses and you're not.  In terms of simple prose style, it always looks to me as if the biggest influences on me are the Sherlock Holmes stories and J.D. Salinger.  In both cases, you have a very cinematic, observed presentation of the action, with a lot of importance given to the dialogue. I can't say who influenced my "subjective" passages, though, or my descriptions, or any of the interior dialogue.  I suspect Raymond Chandler had something to do with the structure.  While I was writing the book, I read "Little Dorrit," which was a big help, though I couldn't say in exactly what way.  Slowed me down, I think.  I kept wanting to get to the point. The book would have been six pages long.

If I had to pin down the most direct influence, I'd say it was comic books: specifically Chris Claremont and John Byrne's "X-Men" of the late 70's and early 80's, and Barry Windsor-Smith's later "Weapon X."   In terms of Who, I'm a Holmes and Hinchcliffe partisan.  Like most Americans, I was introduced to the show in the early 80's via the Tom Baker episodes.

I've seen the complete 7th Doctor series, but only glimpses of the other 5.  Until Christmas of 1998, I didn't even know there were such things as "Doctor Who" novels, other than the old Target TV-adaptations.  I submitted my proposal In September 1999 after spending the summer working it up.  So in the few months between those two periods, I found (thank you, eBay) and read (out of order) all of the NA's plus all the EDA's that were in print and available here (which was up to and including "Unnatural History").  A real crash course.  The NA's were what brought me back to "Doctor Who," what made me want to write a novel, particularly the books of Kate Orman and Paul Cornell, so you're going to see that influence there very strongly.  That said, I'm not sure I could pinpoint exactly what that influence is--again, because I'm in the middle.  The NA's just seemed to me like what Doctor Who books "were" and I wrote accordingly.