There are references yes. His revelation about where he really comes from is a nod in that the Joker has always been an enigma. The failed comedian bit is straight outta The Killing Joke. And in The Dark Knight Returns, he does go on a tv show posing as a reformed version of himself before, if I recall correctly, gassing the audience.
But like the Nolan films, the movie is its own thing. Takes some nods to the source material but an original take on it.
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