@article{jasa85ff,
    title     = {A Fast Field Model for Three-Dimensional Wave Propagation in Stratified
                Environments Based on the Global Matrix Method},
    author    = {Henrik Schmidt and J. Glattetre},
    journal   = {Journal Acoustical Society of America},
    pages     = {2105--2114},
    volume    = {78},
    year      = {1985}}