@article{10_4153_CMB_1993_011_0,
     author = {Krisztin, T. and Mathsen, R. M. and Yuantong, Xu},
     title = {Counterexamples to a {Conjecture} for {Neutral} {Equations}},
     journal = {Canadian mathematical bulletin},
     pages = {74--77},
     year = {1993},
     volume = {36},
     number = {1},
     doi = {10.4153/CMB-1993-011-0},
     url = {http://geodesic.mathdoc.fr/articles/10.4153/CMB-1993-011-0/}
}