@book{28577,
	author = {Trochim, William M.K.},
	title = {Research methods},
	publisher = {Biztantra},
	year = {2009},
	address = {New Delhi},
	edition = {2nd},
	url = {https://libgen.is/book/index.php?md5=B0F15B9F72E025AEFD4CDDEF98FF7D08}
}