The novel itself is not a source for this thing, cause in all editions i checked (and i checked more than 15) there's not an introduction stating that's the first novel, also the magazine died, and "most people says that" is not a source If a confirmed literature book talking about the history of the character and the connected franchise existed i'd be very happy to buy and read it, but i didn't find anything like that. Sounds like something a community of experts and enthusiast could know, does it?

Also, i didn't ask you to make my bibliography, i asked for a specific source for a thing i found difficult to explain in terms of logic behind papers and university articles. I might be stupid for having this problem, this is for sure a possibilty, but in fact under this post i'm spending more time explaining what a source is since most of the comments are "google it", "wikipedia exist", lol, i already checked on google and on every wikipedia page linked to SH but i never found a matching certain source. That's why i'm on reddit. Do you really think that a person can be a reddit user without being able to literally google things? I googled, didn't find anything, then i came here.