@book{171815,
	author = {Schulz, G. E. and Schirmer, R. H., coaut.},
	title = {Principles of protein structure  /},
	publisher = { Springer-Verlag,},
	year = {1979},
	address = {New York  :},
	edition = {2a ed.},
	note = {El ejemplar 2 es material fotocopiado}
}