@article{10_21136_MB_2018_0112_17,
     author = {Petrich, Mario},
     title = {A semilattice of varieties of completely regular semigroups},
     journal = {Mathematica Bohemica},
     pages = {1--14},
     publisher = {mathdoc},
     volume = {145},
     number = {1},
     year = {2020},
     doi = {10.21136/MB.2018.0112-17},
     mrnumber = {4088688},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.21136/MB.2018.0112-17/}
}