Based on a classical and notorious books on ceremonial black magic and summoning, The Grimorium Verum discusses demons, demonology and the dark arts. Containing a catalog of demons and methods of their summoning, it is an up-to date version that is easier to work with.
Grimorium Verum by Joseph H. Peterson combines French and Italian texts on this subject, so a more complete interpretation is available in this book. This modernized text includes useful methods of ritual, an outline of demonic theology, and extensive notation on these subjects. If you are interested in summoning or ceremonial magic this book would be a great addition to your library.
As one reviewer stated: “The Grimorium Verum is one of the more reputable sources of Medieval Christian demonology, specifically drawing from French and Italian heritages. In his translation, Joseph Peterson does not simply choose one text to draw from but rather combines several versions, looking to create a sort of “master version” of the text using the French and even disparate Italian versions.
Between these three he not only compiles both nearly lost texts but through diligent sourcing and constant citation manages to create linkages and suggest connections between the text that may be lost on someone who is not prepared to slog through two languages to try and draw those connections him or herself.”
You can read more about Joseph H Peterson and his works on Ceremonial Magick at his Author Spotlight page.