Nagiza F. Samatova, William Hendrix, John Jenkins, Kanchana Padmanabhan, and Arpan Chakraborty. 2013. Practical Graph Mining with R. Chapman & Hall/CRC.
K Minimum Spanning Tree https://en.wikipedia.org/wiki/K-minimum_spanning_tree
Minimum spanning tree Prim's algorithm https://www.geeksforgeeks.org/prims-minimum-spanning-tree-mst-greedy-algo-5/
Kruskal’s Minimum Spanning Tree Algorithm | Greedy Algo-2 https://www.geeksforgeeks.org/kruskals-minimum-spanning-tree-algorithm-greedy-algo-2/