  We apply the Riccati-Pad\'{e} method and the Rayleigh-Ritz method with
complex rotation to the study of the resonances of a one-dimensional well with
two barriers. The model exhibits two different kinds of resonances and we
calculate them by means of both approaches. While the Rayleigh-Ritz method
reveals each set at a particular interval of rotation angles the Riccati
Pad\'{e} method yields both of them as roots of the same Hankel determinants.
