Take a photo of a barcode or cover
After reading the first two books, this one was a bit frustrating. Different artist, plus the writer kept going off on weird poetic tangents, long sections with no plot, just long boring philosophical musings and art. Definitely the weakest of the first three books.
Of the Alan Moore that I've read, which is admittedly not nearly all, I am inclined to think that this is the maybe his purest expression of a super hero, followed through to its logical conclusion. You can see where ideas for Dr Manhattan, V, and Swamp Thing started to take shape. I have no doubt that Neil Gaiman's follow up is wonderful and imaginative, but I can't imagine it following this.