ebrary, Inc, Classen, A., & Sandidge, M. (2010). Friendship in the Middle Ages and early modern age: Explorations of a fundamental ethical discourse. Walter de Gruyter.
芝加哥风格引文ebrary, Inc, Albrecht Classen, 与 Marilyn Sandidge. Friendship in the Middle Ages and Early Modern Age: Explorations of a Fundamental Ethical Discourse. Berlin ; New York: Walter de Gruyter, 2010.
MLA引文ebrary, Inc, et al. Friendship in the Middle Ages and Early Modern Age: Explorations of a Fundamental Ethical Discourse. Walter de Gruyter, 2010.
警告：这些引文格式不一定是100％准确.