@article{DMGT_2010_30_2_a0,
     author = {Lu, You and Hou, Xinmin and Xu, Jun-Ming},
     title = {On the (2,2)-domination number of trees},
     journal = {Discussiones Mathematicae. Graph Theory},
     pages = {185--199},
     publisher = {mathdoc},
     volume = {30},
     number = {2},
     year = {2010},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/DMGT_2010_30_2_a0/}
}