@article{VMUMM_2010_2_a6,
     author = {V. I. Tsygankov},
     title = {Equations of $G$-minimal conic bundles with degree $4$},
     journal = {Vestnik Moskovskogo universiteta. Matematika, mehanika},
     pages = {39--42},
     publisher = {mathdoc},
     number = {2},
     year = {2010},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/VMUMM_2010_2_a6/}
}