Historian at the University of Louvain, Belgium, Kristof Smeyers, has written books on varied subjects such as economic history, the histories of animals such as ravens and wolves, and supernatural bodies in the 19th and 20th centuries. He has looked into modern cases of stigmata - bodily marks, scars, or pains that appear on a person in the same places as the wounds of Jesus Christ during his crucifixion, and the controversy created when they appear on individuals.