OSE Encounter Activity Tables     Any (no source link)
Monster Manual     D&D 4e (no source link)
Dungeons And Dragons Essentials: Monster Vault     D&D 4e (no source link)
D&D 2e Monstrous Manual     D&D 2e (no source link)
Monstrous Manual: Dragonlance     D&D 2e (no source link)
Scruffy Grognard's Monstrous Manual     D&D 2e (no source link)
AD&D Monster Manual     AD&D 1e (no source link)