The final spot on the classic crime curriculum

Yesterday I posted the nine of the books that would form the Classic Crime Fiction Curriculum - a list of must read, pre-1970 crime novels. There is one space left on the list. The following books all came joint tenth, but I can only pick one. The question is which one? Which of these fifteen books is an ideal complement to the nine already selected? Let me know your choice and the reason why and, based on the responses, I'll select the tenth book for the curriculum.

John Buchan. The Thirty Nine Steps
James Cain, Double Indemnity
Wilkie Collins, The Moonstone
Wilkie Collins, The Woman in White
Edmund Crispin, The Moving Toyshop
Agatha Christie, Five Little Pigs
Agatha Christie, Murder at the Vicarage
Ngaio Marsh, A Surfeit of Lampreys
Ross Macdonald, The Moving Target
Edgar Allen Poe, Murders in the Rue Morgue
Dorothy L. Sayers, Gaudy Night
Maj Sjowall and Per Wahloo, Roseanna
Mickey Spillane, I, The Jury
Josephine Tey, The Daughter of Time
Cornell Woolrich, The Bride Wore Black