600 Voices for the DX7, Amsco Publications, 1987

Rare book which is full of patch ideas for theYamaha DX7 DX5 TX7 TX816 TX216 TF1 and DX1

600 Voices for the DX7
Amsco Publications, London/New York/Sydney/Cologne 1986
ISBN (US) 0-8256-2499-1 (UK) 0-7119-1166-5
204 pages

The patches can be found here (Thanks, Tim Conrardy). The extensions are .snd, but they are just ordinary sysex files.