@article{10_1017_S0017089511000504,
     author = {QIAO, HUSHENG and WANG, LIMIN},
     title = {ON {FLATNESS} {COVERS} {OF} {CYCLIC} {ACTS} {OVER} {MONOIDS}},
     journal = {Glasgow mathematical journal},
     pages = {163--167},
     year = {2012},
     volume = {54},
     number = {1},
     doi = {10.1017/S0017089511000504},
     url = {http://geodesic.mathdoc.fr/articles/10.1017/S0017089511000504/}
}