@article{ZNSL_1970_18_a1,
     author = {T. A. Tushkina and K. V. Shakhbazyan},
     title = {On the main conceptions of parallel ordering},
     journal = {Zapiski Nauchnykh Seminarov POMI},
     pages = {6--15},
     publisher = {mathdoc},
     volume = {18},
     year = {1970},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/ZNSL_1970_18_a1/}
}