Izvornik: Theory Games for Windows. Theory Games for Windows. Games. version 1.5. - Levels 3, 4, 5. Piano Method sheet music.
Prijevod: Teorija igre za Windows. - Razine 3, 4, 5 skladao Willard A. Palmer, Morton Manus, Amanda Vick Lethco, i Rob Wren. Srednji.