@article{SF_1995__50_3_135391,
     author = {A.V. Kelarev},
     title = {Applications of epigroups to graded ring theory.},
     journal = {Semigroup forum},
     pages = {327--350},
     publisher = {mathdoc},
     volume = {50},
     number = {3},
     year = {1995},
     zbl = {0824.16031},
     url = {http://geodesic.mathdoc.fr/item/SF_1995__50_3_135391/}
}