Sakalauskas, Darius, and Aivaras Poška. 2020. “The Organization of Trade in Nemunas from the Riverhead Ports of the Radziwiłł and Sapieha Families in the 1760s and 1770s”. Lietuvos Istorijos Studijos 45 (July): 61-78. https://doi.org/10.15388/LIS.2020.45.6.