@article{MZM_1999_66_6_a1,
     author = {A. I. Degtyarev and V. I. Zvonilov},
     title = {Rigid isotopy classification of real algebraic curves of bidegree $(3,3)$ on quadrics},
     journal = {Matemati\v{c}eskie zametki},
     pages = {810--815},
     publisher = {mathdoc},
     volume = {66},
     number = {6},
     year = {1999},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/MZM_1999_66_6_a1/}
}