@article{AL_1970_9_5_a3,
     author = {L. L. Maksimova},
     title = {$E$-theories},
     journal = {Algebra i logika},
     pages = {530--538},
     publisher = {mathdoc},
     volume = {9},
     number = {5},
     year = {1970},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/AL_1970_9_5_a3/}
}