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Trigonometric Series (in Russian),
Izdat. Fiz.-Mat. Lit., Moscow, 1961.
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3. translation in Sov. Math., Dokl. 15 (1974), 67-71.
4. L. D. Gogoladze,
Uniform strong summation of multiple trigonometric Fourier series (in Russian),
Reports of the Extended Sessions of a Seminar of the I. N. Vekua Institute of Applied Mathematics, Vol. I, no. 2,
Tbilis. Gos. Univ., Tbilisi (1985), 48–51.
5. L. Gogoladze and R. Meskhia,
On the absolute convergence of trigonometric Fourier series,
Proc. A. Razmadze Math. Inst. 141 (2006), 29–40.