Author
British Trust for Ornithology
2
Irish Wildbird Conservancy
2
Sharrock, J. T. R. (John Timothy Robin), 1937-
2
British Trust for Ornithology. Ringing and Migration Committee
1
Brown, Leslie, 1917-
1
Gillmor, Robert
1
Holden, Peter
1
Lack, Peter
1
Mass-Observation
1
Mass-Observation Archive
1
O'Connor, Raymond J.
1
Shrubb, Michael
1
Soper, Tony
1