Published in Bonner Zoologische Beiträge, in 1998, in volume 48, pages 179-203

Created: 2014-05-26, modified: 2014-05-26

Published in Bulletin of The British Ornithologists' Club, in 2003, in volume 123, issue 4, pages 280-285

Created: 2015-08-11, modified: 2015-08-11

Published in Scopus, in 1990, in volume 14, pages 24-25

Created: 2014-03-20, modified: 2014-03-20

Published in Bulletin of The British Ornithologists' Club, in 1981, in volume 101, pages 355-363

Created: 2012-12-03, modified: 2012-12-03