Real property owned by a corporation or association organized exclusively for bible, tract, benevolent, missionary, infirmary, public playground, scientific, literary, bar association, medical society, library, patriotic or historical purposes, for the development of good sportsmanship for persons under the age of eighteen years through the conduct of supervised athletic games, for the enforcement of laws relating to children or animals, or for two or more such purposes, and used exclusivety for carrying out one or more such purposes.
