APA

Williston Samuel,, . (1191). A treatise on the law of contracts Vol. II. New York: West Group.

Chicago

Williston Samuel,, . 1191. A treatise on the law of contracts Vol. II. New York: West Group.

Harvard

Williston Samuel,, . (1191). A treatise on the law of contracts Vol. II. New York: West Group.

MLA

Williston Samuel,, . A treatise on the law of contracts Vol. II. New York: West Group. 1191.