Published in Historia naturalis bulgarica, in 1998, in volume 9, pages 19-26

Published in Historia naturalis bulgarica, in 1998, in volume 9, pages 27-34

Published in Historia naturalis bulgarica, in 1998, in volume 9, pages 35-51

Published in Historia Naturalis Bulgarica, in 1998, in volume 9, pages 53-69

Published in Historia Naturalis Bulgarica, in 1998, in volume 9, pages 71-77

Published in Historia naturalis bulgarica, in 1998, in volume 9, pages 79-86

Published in Historia Naturalis Bulgarica, in 1998, in volume 9, pages 87-99

Published in Historia naturalis bulgarica, in 1998, in volume 9, pages 101-113

Published in Historia naturalis bulgarica, in 1998, in volume 9, pages 129-142