@article{PDM_2017_4_a5,
     author = {M. B. Abrosimov and O. V. Modenova},
     title = {On minimal vertex $1$-extensions of path orientation},
     journal = {Prikladna\^a diskretna\^a matematika},
     pages = {89--94},
     publisher = {mathdoc},
     number = {4},
     year = {2017},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/PDM_2017_4_a5/}
}