中国科学院数学与系统科学研究院期刊网
AMS
The Roman k-domatic Number of a Graph
Seyed Mahmoud SHEIKHOLESLAMI, Lutz VOLKMANN
Acta Mathematica Sinica . 2011, (10): 1899 -1906 .  DOI: 10.1007/s10114-011-0385-0