Exact and approximate complex potentials for modelling time observablesA. Ruschhaupt, J. A. Damborenea, B. Navarro, J. G. Muga and G. C. HegerfeldtEurophys. Lett., 67 1 (2004) 1-7DOI: https://doi.org/10.1209/epl/i2004-10046-4
