River lamprey, Lampetra fluviatilis L., fishery in Latvia – insight into the origin of catch statistics data
Abersons, Kaspar, Birzaks, Jānis
Anthropogenic Influence on the Dynamics of the River Lamprey Lampetra fluviatilis Landings in the River Daugava Basin
Birzaks, Janis, Abersons, Kaspars
Long-term Changes in the Ichthyofauna of Latvia's Inland Waters
Aleksejevs, Eriks, Birzaks, Janis
Occurrence and distribution of fish in rivers of Latvia
Birzaks, Jānis, Aleksejevs, Ēriks, Strūgis, Māris