@article{IVM_2002_8_a5,
     author = {\'E. A. Mirzakhanyan},
     title = {Construction of infinite-dimensional relative homotopy groups in {a~Hilbert} space},
     journal = {Izvesti\^a vys\v{s}ih u\v{c}ebnyh zavedenij. Matematika},
     pages = {43--52},
     year = {2002},
     number = {8},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/IVM_2002_8_a5/}
}