This monumental work (the first four volumes) were created from translations from the Mennonitisches Lexicon and original articles written by Mennonite scholars, pastors and lay leaders primarily from North America and Europe. I have actually read virtually all of it since I was part of a team that helped to incorporate it into the Global Anabaptist Mennonite Encyclopedia Online in the late 1990s and early 2000s at http://www.gameo.org/. A fifth volume supplement was published in 1990 and is also incorporated into the online encyclopedia.