The Science Fiction Source Book is a book by David Wingrove published in 1984.
It is a reference work which grades over 2500 books by 880 authors by giving them ratings of up to 5 stars in the categories of Readability, Characterization, Idea Content and Literary Merit.
[1] Dave Langford reviewed The Science Fiction Source Book for White Dwarf #59, and stated that "This is a game with no ending.
The Sourcebook is enormous fun for browsing in, raising your eyebrows at, and violently disagreeing with.
Just don't trust those stars!