@book{7301,
	author = {Maxon, William R.},
	title = {A study of certain Mexican and Guatemalan species of Polypodium.},
	publisher = {Govt. print. off.,},
	year = {1903.},
	series = {Smithsonian institution.  United States national museum.  Contributions from the United States national herbarium.},
	address = {Washington,}
}