Complete Instrumental Parts to 81 Orchestral Masterworks on CD-ROM.
Contents:

55 Works by Mozart: 16 symphonies, 14 piano concertos, 3 violin concertos, 12 Serenades/Divertimentos, Requiem, Mass in C Major, Mass in C Minor, and 8 opera overtures.

26 Works by Hayden: 23 symphonies, The Creation, The Seasons