1. Sur l’intégrabilité de certaines séries trigonométriques;Aljančić, S.;Acad. Serbe Sci. Publ. Inst. Math.,1955
2. Integrability of trigonometric series. III;Boas, R. P., Jr.;Quart. J. Math. Oxford Ser. (2),1952
3. T. W. Chaundy and A. E. Jolliffe, The uniform convergence of a certain class of trigonometric series, Proc. London Math. Soc. (2), 15 (1916), 214-216.
4. Cambridge Tracts in Mathematics and Mathematical Physics, No. 38;Hardy, G. H.,1944
5. A note on quasi-monotone series;Shah, S. M.;Math. Student,1947