@article{RM_1973_28_5_a6,
     author = {I. I. Parovichenko},
     title = {On the general theory of operations on sets},
     journal = {Trudy Matematicheskogo Instituta imeni V.A. Steklova},
     pages = {133--160},
     publisher = {mathdoc},
     volume = {28},
     number = {5},
     year = {1973},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/RM_1973_28_5_a6/}
}