Leizhen Cai, Derek G. Corneil. Tree Spanners. SIAM J. Discrete Math., 8(3):359-387, 1995. [doi]
@article{CaiC95:0,
title = {Tree Spanners},
author = {Leizhen Cai and Derek G. Corneil},
year = {1995},
url = {http://epubs.siam.org/sam-bin/dbq/article/23740},
researchr = {https://researchr.org/publication/CaiC95%3A0},
cites = {0},
citedby = {0},
journal = {SIAM J. Discrete Math.},
volume = {8},
number = {3},
pages = {359-387},
}