Discus Fish (Complete Pet Owner's Manual)
Jack Wattley's Handbook of Discus/H1070
Schmidt-Fockes Discus Book
Discus for the Perfectionist
Discus a Reference Book
Degen Discus Book
Trophy Discus: The art of selecting, grooming, and showing discus.
Discus Health: Selection, Care, Diet, Diseases & Treatments for Discus, Angelfish and Other Cichlids
The Atlas of Discus of the World
Discus in the Community Tank