@article{PFMT_2014_3_a1,
     author = {N. A. Akhramenko and L. M. Bulauko},
     title = {Mass of massive spherical shell with regard to gravitational defect},
     journal = {Problemy fiziki, matematiki i tehniki},
     pages = {13--15},
     publisher = {mathdoc},
     number = {3},
     year = {2014},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/PFMT_2014_3_a1/}
}