1939 novel by Raymond Chandler, the first to feature Philip Marlowe (3,3,5)

I believe the answer is:

the big sleep

(Other definitions for the big sleep that I've seen before include "No catnap" , "[BACALL & BOGART] in this!" , "Raymond Chandler book" , "Raymond Chandler novel, Bogart film" , "Bogart/Bacall film of 1946" .)

I've seen this clue in The Independent.

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