Cita APA (7th ed.)
Guth, H. P. (1969). Words and ideas (3rd ed.). Wadsworth.
Cita Chicago (17th ed.)
Guth, Hans P. Words and Ideas. 3rd ed. Belmont, California: Wadsworth, 1969.
Cita MLA (9th ed.)
Guth, Hans P. Words and Ideas. 3rd ed. Wadsworth, 1969.
Atenció: Aquestes cites poden no estar 100% correctes.