Published in Biol Bull, in 1959, in volume 117, pages 347-355

Created: 2010-01-06, modified: 2011-06-21

Published in Mammal Study, in 1997, in volume 22, pages 45-52

Created: 2014-09-25, modified: 2014-09-25

Published in Journal of Raptor Research, in 1994, in volume 28, issue 3, pages 171-177

Created: 2017-04-07, modified: 2017-04-07

Published in Zoological Science, in 1993, in volume 10, pages 497-504

Created: 2012-09-19, modified: 2012-09-19

Published in Zoological Science, in 1993, in volume 10, pages 353-360

Created: 2012-09-19, modified: 2012-09-19

Published in Zoological Science, in 1990, in volume 7, pages 141-145

Created: 2012-09-19, modified: 2012-09-19