Davis, H. A. a. C. (1933). Brief course in plane and sperical trigonometry. American Book.
Chicago-viite (17. p.)Davis, H. A. and Chambers. Brief Course in Plane and Sperical Trigonometry. New ork: American Book, 1933.
MLA-viite (9. p.)Davis, H. A. and Chambers. Brief Course in Plane and Sperical Trigonometry. American Book, 1933.
Varoitus: Nämä viitteet eivät aina ole täysin luotettavia.