@book{95116,
	author = {Ferri, Enrico, and Payró, Roberto Jorge,},
	title = {Socialismo y ciencia positiva (Darwin-Spencer-Marx)},
	publisher = {Project Gutenberg,},
	year = {2017},
	address = {Salt Lake City, UT :},
	note = {Release date is 2017-03-04},
	url = {https://www.gutenberg.org/ebooks/54282}
}