@book{28922,
	author = {Valkenburg, M.E. Van},
	title = {Network analysis},
	publisher = {PHI Learning},
	year = {1974},
	address = {New Delhi},
	edition = {3rd},
	url = {https://libgen.is/book/index.php?md5=62FCE878E72415CF8195A8274DA89818}
}