[1] S. Peng, A.B. Stephens, Y. Yesha,” Algorithms for a core and a tree core of a tree”, J. Algorithms Vol. 15, pp. 143-159, (1993).
[2] A. Shioura and T. Uno, “Alinear time algorithm for finding a k-tree core”, J Algorithms, Vol. 23 pp. 281- 290, (1997).
[3] R.I. Becker, I. Lari, G. Storchi, A. Scozzari, “Efficient algorithms for finding the core of tree networks”, Networks Vol. 40(4), pp. 208-251, (2002).
[4] B. Wang, S.Peng, H.Yu and S.Ku,” Efficient algorithms for a constrained k-tree core problem in a tree network”, Journal of Algorithms, Vol. 59, pp. 107-124, (2006).
[5] J. Puerto, F. Ricca and A. Scozzari, “Reliability problems in multiple path-shaped facility location on networks”, Discrete Optimization, Vol. 12, pp. 61-72, (2014).
[6] S. Peng, W. Lo, “Efficient algorithms for finding a core of a tree with a specified length”, J. Algorithms,Vol. 20, pp. 445-458, (1996).