Xinmin Hou, You Lu, Jun Ming Xu. On the (2, 2)-domination number of trees. Discussiones Mathematicae Graph Theory, 30(2):185-199, 2010. [doi]
@article{HouLX10,
title = {On the (2, 2)-domination number of trees},
author = {Xinmin Hou and You Lu and Jun Ming Xu},
year = {2010},
url = {http://www.uz.zgora.pl/discuss/gt/30_2/gt30-635.htm},
researchr = {https://researchr.org/publication/HouLX10},
cites = {0},
citedby = {0},
journal = {Discussiones Mathematicae Graph Theory},
volume = {30},
number = {2},
pages = {185-199},
}