@article{ZNSL_1975_49_a6,
     author = {R. I. Freidson},
     title = {Finite approximation approach to investigation of the complexity of recursive predicates},
     journal = {Zapiski Nauchnykh Seminarov POMI},
     pages = {131--158},
     publisher = {mathdoc},
     volume = {49},
     year = {1975},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/ZNSL_1975_49_a6/}
}