| Author: | Nagięc, M., and L. Pirtań |
| Article Title: | Variation in the number of vertebrae in several year-classes in European pike-perch (Stizostedion lucioperca (L)) in Jeziorak Lake, Mazurian Lake District |
| Keywords: | Stizostedion lucioperca, European pike-perch, Jeziorak Lake, Poland, morphology, vertebrae, Sander lucioperca |