History: Batman and Superman — Partners, Fighters, Bed Sharers

The Man of Steel sequel will feature DC Comic's most prominent superheroes. They've met many times before.

Comics 411: Favorite Superhero Rivalries

Super Sons Vol. 3: Parent Trap by Peter J. Tomasi: 9781401284466

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The best legacy superheroes in comic books

DC Universe Animated Original Movies (Part 46): Batman & Superman: Battle Of The Super Sons – Casual Comix Critique

Are Batman and Superman rivals? Why or why not? - Quora

DC Has Revisited (and Revised) Batman and Superman's First Meeting — Yet Again

Comic Book Court: Batman vs. Romance

Comic Excerpt] Superman and Batman meet for the first time in Man of Steel #3 — how would you want to see these two characters meet in the DCU? : r/DCcomics

Taking the Batman out of the shadows

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Composite Superman (Character) - Comic Vine