1. Graduate Texts in Mathematics;F. Albiac,2006
2. Bessaga, C., Pełczyński, A.: On basis and unconditional convergence of series in Banach spaces. Stud. Math. 17, 151–164 (1958) http://eudml.org/doc/216910
3. Faried, N., Abd El Kader, Z., Mehanna, A.A.: s-numbers of polynomials of shift operators on $\ell ^{p}$ spaces $1\leq p \leq \infty $. J. Egypt. Math. Soc. 1, 31–37 (1993)
4. Faried, N., Harisa, S.A.: Wide class of Banach spaces in which Grothendieck conjecture holds. Glob. J. Pure Appl. Math. 12(6), 5059–5077 (2016) http://www.ripublication.com/gjpam.htm
5. Knopp, K.: Theory and Application of Infinite Series. Blackie and Son Limited, London (1951)