Peters, M., & Schaaf, W. L. (1967). Mathematics: A modern approach (2nd ed.). Van Nostrand Reinhold.
Cita Chicago (17th ed.)Peters, Max, i William Leonard Schaaf. Mathematics: A Modern Approach. 2nd ed. Princeton, N.J: Van Nostrand Reinhold, 1967.
Cita MLA (9th ed.)Peters, Max, i William Leonard Schaaf. Mathematics: A Modern Approach. 2nd ed. Van Nostrand Reinhold, 1967.
Atenció: Aquestes cites poden no estar 100% correctes.