Sprinkhuizen- Kuyper, I. G. (1979). Koornwinder polynomials: A special class of orthogonal polynomials in two variables. s.n.].
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रSprinkhuizen- Kuyper, Ida Gerda. Koornwinder Polynomials: A Special Class of Orthogonal Polynomials in Two Variables. [S.l.: s.n.], 1979.
एमएलए (8वां संस्करण) प्रशस्ति पत्रSprinkhuizen- Kuyper, Ida Gerda. Koornwinder Polynomials: A Special Class of Orthogonal Polynomials in Two Variables. s.n.], 1979.
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