Hengartner, W., & Theodorescu, R. j. a. (1973). Concentartion functions. Academic Press.
Cita Chicago (17th ed.)Hengartner, Walter, i Radu joint auth Theodorescu. Concentartion Functions. New York: Academic Press, 1973.
Cita MLA (9th ed.)Hengartner, Walter, i Radu joint auth Theodorescu. Concentartion Functions. Academic Press, 1973.
Atenció: Aquestes cites poden no estar 100% correctes.