Well, to clarify then, I mentioned the "beat generation" because those are the writers that get mention here all the time, and Selby is more-or-less the same age group as many of them
and he's an American writer. And although you have no idea because you're new, I've often made the exact point that "Last Exit to Brooklyn" is every bit as iconic in 20th c. American Lit as "On the Road" is in an attempt to try to turn people here onto it. Oh, and because I think I'm "cultured." (like some douche wrote once)
The same goes for more other things than I can list, and I've been doing this for years.
I have the paperback from a used book store with the original cover. Just a stating a fact. But, yes, it is cooler than the other covers though.
'70s Creem contributor Nick Toscheshas ascribed "Last Exit to Brooklyn" the importance of being to the 20th c. what Melvilles' "Moby Dick" was to the nineteenth. He's done some a spoken word album with Selby and one with Patti Smith.
http://www.exitwounds.com/Hubert-Selby-Jr.htm