Machado, J. A. TenreiroGalhano, AlexandraTrujillo, Juan J.2014-02-062014-02-0620140138-91301588-2861http://hdl.handle.net/10400.22/3769Fractional calculus generalizes integer order derivatives and integrals. During the last half century a considerable progress took place in this scientific area. This paper addresses the evolution and establishes an assertive measure of the research development.engFractional calculusScientific evolutionScience metricsOn development of fractional calculus during the last fifty yearsjournal article10.1007/s11192-013-1032-6