@book{19557,
	author = {Biological Sciences Curriculum Study. and Welch, Claude A.},
	title = {Biological science :},
	publisher = {Harcourt Brace Jovanovich,},
	year = {1973.},
	series = {Houghton Mifflin science program},
	address = {New York :},
	edition = {3d ed.}
}