닭의 목아지를 비틀어도 새벽은 온다. - 1979, 김영삼 -
Convergence of Correlations
http://faculty.ucr.edu/~hanneman/nettext/C13_%20Structural_Equivalence.html Breiger et al. 1974 structural_equivalence.doc also UCINET help file http://www.sciencedirect.com/science/article/pii/0022249675900280