Most northerly record of the bighead goby Ponticola kessleri (Günther, 1861) in the Elbe River, Germany Thiel, Ralf Schulze, S. Hempel, M. Husemann, Martin 2017 - Forschungsinformationssystem der UHH
First records of the round goby Neogobius melanostomus (Pallas, 1814) in the Elbe River, Germany Hempel, M. Thiel, Ralf 2013 - Forschungsinformationssystem der UHH