@book {534,
	title = {Red Data Books of Britain and Ireland: lichens},
	series = {Britain},
	volume = {1},
	year = {1996},
	publisher = {Joint Nature Conservation Committee},
	organization = {Joint Nature Conservation Committee},
	address = {Peterborough},
	author = {Church, J.M. and Coppins, B.J. and Gilbert, O.L. and James, P. and Stewart, N.F.}
}
@article {231,
	title = {Field evidence for an acid rain effect on lichens},
	journal = {Environmental Pollution},
	volume = {40},
	year = {1986},
	pages = {227-231},
	author = {Gilbert, O.L.}
}
@article {55,
	title = {Environmental effects of airborne fluorides for aluminium smelting at Invergordon, Scotland 1971-1983},
	journal = {Environmental Pollution (Series A)},
	volume = {39},
	year = {1985},
	pages = {293-302},
	author = {Gilbert, O.L.}
}
@article {230,
	title = {Bryophytes as indicators of air pollution in the Tyne valley},
	journal = {New Phytologist},
	volume = {69},
	year = {1968},
	pages = {629-634},
	author = {Gilbert, O.L.}
}
@article {229,
	title = {Lichens as indicators of air pollution in the Tyne Valley},
	year = {1965},
	pages = {pp35-49},
	author = {Gilbert, O.L.},
	editor = {Goodman, G.T. and Edwards, R.W. and Lambert, J.M.}
}
