@article{PDM_2020_4_a6,
     author = {L. X. Hung},
     title = {The chromaticity of the join of tree and null graph},
     journal = {Prikladna\^a diskretna\^a matematika},
     pages = {93--101},
     year = {2020},
     number = {4},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/PDM_2020_4_a6/}
}