@article{IVM_2007_3_a3,
     author = {N. Kehayopulu and M. Tsingelis},
     title = {Semilattice composition of ordered semigroups},
     journal = {Izvesti\^a vys\v{s}ih u\v{c}ebnyh zavedenij. Matematika},
     pages = {29--37},
     publisher = {mathdoc},
     number = {3},
     year = {2007},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/IVM_2007_3_a3/}
}