Heading down the rabbit hole…
Qwikiverse maps the references between stories: what Detective Comics #27 (Batman debut) nods to, and what nods back. How it works
Wikipedia: Detective Comics 27 (May 1939).png
"Batman, a History of Heroics: The Beginning" at DC Comics. Retrieved April 20, 2019.
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Nothing spotted here yet.
A line quoted, a cameo, a character named after something: if Detective Comics #27 (Batman debut) nods to another story, or another story nods to it, spot the first one.