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