Degree of Approximation of Functions by Nörlund Summability of Double Fourier Series

Degree of Approximation of Functions by Nörlund Summability of Double Fourier Series

In this research paper, the author studies some problems which are relating to harmonic summability of double Fourier series on Nörlund summability. These results constitute substantial extension and generalization of related works of F. Moricz and B.E Rhodes [1] and H.K. Nigam and K. Sharma [2].

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