BIRD STUDY VOLS. 23-24
Written by Kenneth Williamson. Stock no 696268. Published by British Trust for Ornithology. 1976.

BIRD STUDY VOLS. 21-22
Written by Kenneth Williamson. Stock no 696267. Published by British Trust for Ornithology. 1974.

BIRD STUDY VOLS. 19-20
Written by J.J.M. Flegg & Kenneth Williamson. Stock no 696266. Published by British Trust for Ornithology. 1972.

BIRD STUDY VOLS. 15-16
Written by David W. Snow. Stock no 696264. Published by British Trust for Ornithology. 1968.

BIRD STUDY VOLS. 13-14
Written by David W. Snow. Stock no 696263. Published by British Trust for Ornithology. 1966.

BIRD STUDY VOLS. 8-10
Written by J.C. Coulson. Stock no 696261. Published by British Trust for Ornithology. 1961.

BIRD STUDY VOLS. 11-12
Written by J.C. Coulson. Stock no 696262. Published by British Trust for Ornithology. 1964.

BIRD STUDY VOLS. 17-18
Written by J.J.M. Flegg & Kenneth Williamson. Stock no 818243. Published by British Trust for Ornithology. Circa. 1971.

BIRD STUDY VOLS. 13-14
Written by David W. Snow. Stock no 818245. Published by British Trust for Ornithology. Circa. 1967.

BIRD STUDY VOLS. 15-16
Written by David W. Snow. Stock no 818248. Published by British Trust for Ornithology. Circa. 1969.

BIRD STUDY VOLS. 21-22
Written by Kenneth Williamson. Stock no 818244. Published by British Trust for Ornithology. Circa. 1975.

BIRD STUDY VOLS. 11-12
Written by J.C. Coulson. Stock no 818247. Published by British Trust for Ornithology. 1965.