1. K. Diethelm, The Analysis of Fractional Differential Equations (Springer, Berlin, 2010)
2. K.S. Miller, B. Ross, An Introduction to the Fractional Calculus and Fractional Differential Equations (Wiley, New York, 1993)
3. I. Podlubny, Fractional Differential Equations (Academic Press, San Diego, 1999)
4. K.B. Oldham, J. Spanier, The Fractional Calculus (Academic Press, San Diego, 1974)
5. V. Kiryakova, Generalised Fractional Calculus and Applications, in Research Notes in Mathematics, Vol. 301 (Chapman and Hall, 1994)