The Official Crisis on Infinite Earths Cross-Over Index #1 (1986)

Features a comprehensive look at all the Infinite Earths: Earth-One, Earth-Two, Earth-Three, Earth-Four, Earth-Six, Earth-S, Earth-X, Earth-Quality, Earthy-B, Earth-12, Crossover Earth, Earth-C, Earth-C-Minus, and Earth-Prime. Further features include: Index to The Monitor's Pre-Crisis Appearances; covers and content info for all Crisis Crossover and post-Crisis issues; Aphabetical index to ALL Crisis heroes, villains, supporting characters, and innocent bystanders; A Crisis Flowchart: The Continuity of Events in Crisis on Infinite Earths; plus Addenda ad Errata to Crisis on Infinite Earths Index #1.