@book {47,
	title = {The Lichen Flora of Great Britian and Ireland},
	year = {1992},
	publisher = {Natural History Museum Publications},
	organization = {Natural History Museum Publications},
	address = {London},
	author = {O.W. Purvis and D.M. Moore and B.J. Coppins and D.L. Hawksworth and P.W. James}
}
