B.O.U. check-list
British Ornithologists' Union
by M.E.J. Gore
British Ornithologists' Union 1990, c1981 2nd rev. ed. B.O.U. check-list no. 3
Available at 1 libraries
by C.M.N. White & Murray D. Bruce
British Ornithologists' Union c1986 B.O.U. check-list no. 7
Available at 2 libraries
by Peter R. Flint and Peter F. Stewart
British Ornithologists' Union 1983 B.O.U. check-list no.6
British Ornithologistsʾ Union 1981 B.O.U. check-list no. 3
pbk.