TY - JOUR N2 - In the paper, on the basis of several dozen examples of hydronyms from eastern and north-eastern Mazovia, the erroneous attribution of written sources and, as a consequence, their incorrect identification and location were shown. These kinds of mistakes can be found in toponymical, hydrographical and historical publications. It is the result of taking attestations from the context of the source, poor knowledge of the history and the geography of the studied area, as well as the poor knowledge of Latin and the lack of verification of hypotheses found in older literature. L1 - http://journals.pan.pl/Content/115456/PDF-MASTER/Strony%20od%20Onomastica63-07.pdf L2 - http://journals.pan.pl/Content/115456 PY - 2019 EP - 144 KW - hydronymy KW - Eastern Mazovia KW - North-eastern Mazovia A1 - Kowalczyk-Heyman, Elżbieta PB - Komitet Językoznawstwa PAN PB - Instytut Języka Polskiego PAN VL - No 63 DA - 2019.12.30 T1 - About Meanders of Identification of Medieval River Names in the North-eastern and Eastern Mazovia Region SP - 127 UR - http://journals.pan.pl/dlibra/publication/edition/115456 T2 - Onomastica ER -