The Beit Yosef and Joseph Caro's source method

The Beit Yosef is Rabbi Joseph Caro's vast commentary on the Tur, the fruit of twenty years' labor. For each law it traces the sources from the Talmud through the medieval authorities, sets out the disagreements and rules, generally by the majority of the Rif, Maimonides and the Rosh. This monumental work served as the foundation for his abridged code, the Shulchan Arukh.