@book{83409,
	author = {Yrjö-Koskinen, Yrjö Sakari,},
	title = {Johtavat aatteet ihmiskunnan historiassa},
	publisher = {Project Gutenberg,},
	year = {2013},
	address = {Salt Lake City, UT :},
	note = {Release date is 2013-04-21},
	url = {https://www.gutenberg.org/ebooks/42570}
}