“…However, when unknown, the frequency can be estimated by using one of the many approaches suggested in literature [18,42,43]. Exponential fitting techniques have been successfully used to solve problems of very different nature, such as fractional differential equations [7], quadrature [14,16,24], interpolation [21], time and space integrators for ODEs [12,15,41] and PDEs [8,13,19], integral equations [9,10], boundary value problems [32].…”