Day of the Owl, Equal Danger (Godine Double Detective, No. 4)

Double Fudge

The Double Helix: A Personal Account of the Discovery of the Structure of DNA

Double

Double Blinded

Hollow Earth Affair the Royal Pain (Double Agent Books)

Bodie Beauties/Frisco Foxes (Spur Double)

Quartre Ou Double

Double-Crossed in Gator Country (Eric Sterling, Secret Agent, Book 2)

Sailing to Byzantium/Seven American Nights (Tor Doubles, No 10)