@article{SEMR_2021_18_2_a14,
     author = {S. A. Badaev and B. S. Kalmurzayev and N. K. Mukash and A. A. Khamitova},
     title = {Special classes of positive preorders},
     journal = {Sibirskie \`elektronnye matemati\v{c}eskie izvesti\^a},
     pages = {1657--1666},
     publisher = {mathdoc},
     volume = {18},
     number = {2},
     year = {2021},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/SEMR_2021_18_2_a14/}
}