Solid Gold was released by US Gold and contains the following games:

SOLIDG1A.DSK - Infiltrator (US Gold), Ace of Aces (US Gold)
SOLIDG1B.DSK - Leaderboard (US Gold), Ace of Aces (US Gold)
SOLIDG2A.DSK - Gauntlet (US Gold)
SOLIDG2B.DSK - Winter Games (Epyx)

Gauntlet is loaded by typing |CPM. All the other games are loaded by typing
RUN"DISK". To load Ace of Aces, use SOLIDG1A.DSK and then insert SOLIDG1B.DSK.