In the article, Saatchi talks about cannibalism, and the fascination that some people have with it. His first example is Jonathan Swift's satirical work of 1729 A modest proposal. Given the nature of the text (a social satire, suggesting that poor Irish families should sell their children to the English aristocracy for eating), it must have been hard for the Standard's picture editor to find a book cover to accompany it.
What was printed is the cover of the book Eating Children by Dr. J. Swift. However, this book doesn't exist. It was made up by Richard Littler as part of his ongoing humourous hauntology project Scarfolk. Here's our article on Scarfolk, and here's the original on the Scarfolk website.
We assume that because the image was perceived by the Standard to be kosher, Littler wasn't credited for it. We put it to him, and he is cool about it to the point of seeing the funny side. After all, Scarfolk's covers use imagery from elsewhere - which Littler is in the process of fully crediting in the Scarfolk book, to be published later in the year.
Hopefully, Saatchi will also see the funny side and not strangle his picture editor (not that he has ever strangled anyone, of course).