Joel Kramer (born August 9 1937) is an American author. He is especially known as an author of various books and articles about yoga as well as being a co-author with Diana Alstad of two books on modern society and the individual. Given a list of categories: company, educational institution, artist, athlete, office holder, mean of transportation, building, natural place, village, animal, plant, album, film or written work, what category does the paragraph belong to?
A:
Artist