@article{INTG_1969_2_a7,
     author = {G. F. Laptev},
     title = {The structural equations of a~principal bundle manifold},
     journal = {Itogi Nauki i Tekhniki. Seriya Problemy Geometrii. Trudy Geometricheskogo Seminara},
     pages = {161--178},
     publisher = {mathdoc},
     volume = {2},
     year = {1969},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/INTG_1969_2_a7/}
}