Narvalové v moři, Dr. Kristin Laidre, Polar Science Center, UW NOAA/OAR/OER/Public domain, https://commons.wikimedia.org/wiki/File:Pod_Monodon_monoceros.jpg .

Narvalové v moři, Dr. Kristin Laidre, Polar Science Center, UW NOAA/OAR/OER/Public domain, https://commons.wikimedia.org/wiki/File:Pod_Monodon_monoceros.jpg .