(1969). Lectures in differential equations. Van Nostrand Reinhold Co.
Cita Chicago (17th ed.)Lectures in Differential Equations. New York: Van Nostrand Reinhold Co, 1969.
Cita MLA (9th ed.)Lectures in Differential Equations. Van Nostrand Reinhold Co, 1969.
Atenció: Aquestes cites poden no estar 100% correctes.