In 1966 Silverberg began a series of anthologies, each on a prominent theme of science fiction, in sturdy hardcover editions for the library market, proceeding at a rate of one a year. After the first four titles for Meredith Press, the books went to Thomas Nelson and Hawthorne Press, at a rate of one a year for each publisher. After 24 solo volumes (a couple going to yet other publishers), Silverberg went on to support co-editors on four further anthologies, the last three appearing as original paperbacks. A feature of Silverberg's solo volumes was that every one included a Silverberg story.
The photo shows an (incomplete) mix of hardcover first editions (facing outward or semi-outward), book club editions, paperback reprints, and paperback originals of the later volumes.
After Silverberg himself, most-reprinted authors: Poul Anderson (12), Isaac Asimov (9), Brian W. Aldiss and R.A. Lafferty (8 each), Arthur C. Clarke, Philip K. Dick, and Fritz Leiber (7 each).
Earthmen and Strangers, (Meredith Press, 1966)
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