In 1978, having published five issues of the Void Science Fiction and Fantasy, editor Paul Collins transformed the magazine into a series of hardcover original anthologies which were released under the collective 'Worlds' title. The proposed contents for issues 6, 7 and 8 of Void in fact became the contents of the first anthology, Envisaged Worlds. After closing down Void Publications in 1981 Collins published the latter anthologies through his new company, Cory and Collins. A final title in the "worlds" series, Metaworlds, was released in 1994 by Penguin.
[Source: Marshall B. Tymn and Mike Ashley. Science Fiction, Fantasy, And Weird Fiction Magazines, 1985, pp. 266-267]