1 Deng Yaohua, Gu Yonggent. A new class of function space and Hilbert transform. J Math Anal Appl,
1985,108:99-108
2 Hardy G H, Littlewood J E. Some more theorems concerning Fourier and Fourier power series. Duke Math
J, 1936,2:354-382
3 Zygmund A. Trigonometric Series. Cambridge, 1959,2:93