Title: Crisis on multiple earths
Subjects: Graphic Novels - Science Fiction, Fiction - General, Juvenile Fiction, Graphic Novels, Children: Young Adult (Gr. 7-9), Fiction / General, Comics & Graphic Novels - Superheroes, Comic books, strips, etc, Justice League of America (Fictitious characters), Comic books, strips, Justice Society of America (Fictitious characters), Life on other planets, Heroes, Good and evil