@book {103,
	title = {Pollen and Spore Morphology, Plant Taxonomy: Gymnospermae, Pteridophyta, Bryophyta. (Illustrations)},
	year = {1957},
	publisher = {Almqvist \& Wiksell},
	organization = {Almqvist \& Wiksell},
	author = {Erdtman, G.}
}
