@article{ZNSL_2003_299_a20,
     author = {M. A. Stepanova},
     title = {Generic immersions of the two-sphere to $\mathbf R^3$ and their skeleta},
     journal = {Zapiski Nauchnykh Seminarov POMI},
     pages = {300--313},
     publisher = {mathdoc},
     volume = {299},
     year = {2003},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/ZNSL_2003_299_a20/}
}