Sci-Fi must reads?

[javasaurus]

Asimov, Bradbury, Heinlein. These are some of the fathers of sci-fi (where Shelley, Verne, and Wells would be the grandparents). But there are others that are the uncles and aunts. Who do you recommend? James Blish? Poul Anderson? Robert Silverberg? Andre Norton? A.E. Van Vogt?

What authors/books of the 60s and 70s do you think a well-read sci-fi fan should read, but might have missed?

Comments

[javasaurus.livejournal.com]

Why is the name Simak ringing a bell?

Thanks for the names -- they're going on the list! Any particular works you'd suggest?