Per Year

 @article{autopoiesis-biosystems5,
	Author = {Varela, Francisco G. and Maturana, Humberto R. and Uribe, R.},
	Doi = {10.1016/0303-2647(74)90031-8},
	Issn = {0303-2647},
	Journal = {Biosystems},
	Month = may,
	Number = 4,
	Pages = {187--196},
	Title = {Autopoiesis: The Organization of Living Systems, its Characterization and a Model},
	Url = {http://www.sciencedirect.com/science/article/pii/0303264774900318},
	Volume = 5,
	Year = 1974}