Published in Bulletin of The British Ornithologists' Club, in 1933, in volume 54, pages 19-20
Published in Bulletin of the British Ornithologists' Club, in 1933, in volume 53, pages 129-161
Published in Bulletin of The British Ornithologists' Club, in 1933, in volume 53, pages 119-124
Published in Bulletin of the British Ornithologists' Club, in 1933, in volume 53, pages 154