@article{TMF_1987_70_3_a8,
     author = {M. Yu. Logachev},
     title = {Investigation of gauge ambiguity by means of the theory of harmonic maps},
     journal = {Teoreti\v{c}eska\^a i matemati\v{c}eska\^a fizika},
     pages = {412--421},
     publisher = {mathdoc},
     volume = {70},
     number = {3},
     year = {1987},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/TMF_1987_70_3_a8/}
}