@article{GMJ_1998__5_2_48031,
     author = {Hou, Zhanyuan and Cassell, J.S.},
     title = {Asymptotic solutions for mixed-type equations with a small deviation.},
     journal = {Georgian Mathematical Journal},
     pages = {107--120},
     publisher = {mathdoc},
     volume = {5},
     number = {2},
     year = {1998},
     zbl = {0903.34066},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/GMJ_1998__5_2_48031/}
}