This game came in 2 editions, an Expansion Kit edition and a Deluxe edition.
For the expansion kit you must own La Bataille de Ligny and La Bataille des Quatre Bras as it only contains maps, special rules and background. The Deluxe Edition contains those items plus the counters and basic rules.
The Deluxe edition contains:
4 34×22″ maps
3 Organizational Displays
Standard Rules & Special Rulebook
6 Counter Sheets (2 Quatre Bras, 3 Ligny, 1 Informational markers)
Charts & Tables