Published in Bulletin Br Orn Club, in 1974, in volume 94, pages 42-49

Published in Bulletin Br Orn Club, in 1974, in volume 94, pages 69-71

Published in Bulletin Br Orn Club, in 1974, in volume 94, pages 145-150

Published in Bulletin Br Orn Club, in 1974, in volume 94, pages 163-164