@techreport{SiSc05,
address = {\url{http://arxiv.org/}},
author = {Ji{\v{r}}{\'{\i}} {\v{S}}{\'{\i}}ma and Satu Elisa Schaeffer},
institution = {arXiv.org e-Print archive},
month = {June},
number = {cs.CC/0506100},
pages = {9},
title = {On the \np-Completeness of Some Graph Cluster Measures},
type = {Technical Report},
year = {2005},
}