Published in Raptor Research, in 1975, in volume 9, issue 1/2, pages 1-11

Published in Raptor Research, in 1975, in volume 9, issue 1/2, pages 11

Published in Raptor Research, in 1975, in volume 9, issue 1/2, pages 12-17

Published in Raptor Research, in 1975, in volume 9, issue 1/2, pages 18-20

Published in Raptor Research, in 1975, in volume 9, issue 1/2, pages 21-26

Published in Raptor Research, in 1975, in volume 9, issue 1/2, pages 27-32

Published in Raptor Research, in 1975, in volume 9, issue 3/4, pages 33-39

Published in Raptor Research, in 1975, in volume 9, issue 3/4, pages 46-50

Published in Raptor Research, in 1975, in volume 9, issue 3/4, pages 51-54

Published in Raptor Research, in 1975, in volume 9, issue 3/4, pages 55-57

Published in Raptor Research, in 1975, in volume 9, issue 3/4, pages 58-59

Published in Raptor Research, in 1975, in volume 9, issue 3/4, pages 60-64