@article{CMJ_2006__56_4_a1,
     author = {He, Yong and Shao, Fang and Li, Shi-qun and Gao, Wei},
     title = {On left $C$-$\scr U$-liberal semigroups},
     journal = {Czechoslovak Mathematical Journal},
     pages = {1085--1108},
     publisher = {mathdoc},
     volume = {56},
     number = {4},
     year = {2006},
     mrnumber = {2280796},
     zbl = {1157.20334},
     language = {en},
     url = {https://geodesic-test.mathdoc.fr/item/CMJ_2006__56_4_a1/}
}