@book{206907,
	author = {Pettit, R.H. and McDaniel, Eugenia and Michigan Agr. College: Technical Bulletin; 48},
	title = {The lecania of Michigan  /},
	publisher = { Michigan Agricultural College},
	address = {East Lansing, Michigan :},
	note = {Encuadernado con otros impresos similares}
}