I did some searching on the net and found the following:
The full name of the book is "nazaten van Berent Elserman en Derksken Oink op Wilgenhof" and is a publication of the work group genealogy of the foundation "de elf marken" in Gorssel. It contains info of the family Wilgenhof in the area of Zutphen, Almen, Gorssel, etc.
The book, as well as a drawn diagram, is still available. Costs: euro 25 for the book, euro 12 for the diagram, plus postage. You can order it at firstname.lastname@example.org