Hoo-wee! This is a great episode, and it doesn't even have the Justice League!  All-Star Comics (1941) #4, with the first mission of the JSA!  Flash (1960) #123, with the first Golden Age/Silver Age team-up!  Flash (2016) #9, with "Kid Flash of Two Worlds"!  And 2017's Batman #21, Flash #21, Batman #22, and Flash #22: "The Button"!