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Q. If you write “In the opening of Raymond Chandler’s 1940 novel Farewell, My Lovely . . . ,” ought there to be a comma after novel, as it was his only novel published that year and so what follows is a nonrestrictive appositive? Or does that seem too clunky?
A. The comma is correct, but it can be considered optional in contexts where a writer isn’t necessarily privy to the facts that would determine restriction, and where, as you point out, the extra comma would be awkward.