@article{10_21136_CMJ_2019_0335_17,
     author = {Liu, Hailin and Lou, Bengong and Ling, Bo},
     title = {Tetravalent half-arc-transitive graphs of order $p^2q^2$},
     journal = {Czechoslovak Mathematical Journal},
     pages = {391--401},
     publisher = {mathdoc},
     volume = {69},
     number = {2},
     year = {2019},
     doi = {10.21136/CMJ.2019.0335-17},
     mrnumber = {3959952},
     zbl = {07088792},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.21136/CMJ.2019.0335-17/}
}