 African-born Italian Benedictine monk (Muslim convert) Constantine the African (died 1099) of Monte Cassino translated many Arabic medical works into Latin.Spanish Muslim physician Avenzoar (1094–1162) performed the first tracheotomy on a goat, writing "Book of Simplification on Therapeutics and Diet", which became popular in Europe.Spanish Muslim physician Averroes (1126–1198) was the first to explain the function of the retina and to recognize acquired immunity with smallpox.