1. Introduction to spectral theory: selfadjoint ordinary differential operators: selfadjoint ordinary differential operators;Levitan,1975
2. A new definition of fractional derivative;Khalil;J. Comput. Appl. Math.,2014
3. On conformable fractional calculus;Abdeljawad;J. Comput. Appl. Math.,2015
4. Fractional singular Sturm–Liouville operator for coulomb potential;Bas;Adv. Differ. Equ.,2013
5. U.N. Katugampola, A new fractional derivative with classical properties, 2014, arXiv:1410.6535.