Copy of original permafrost map drawn by Karl Ernst von Baer, 1843, published in L. King, 2001
<a href="//commons.wikimedia.org/wiki/User:Matti%26Keti" title="User:Matti&amp;Keti">Matti&amp;Keti</a>
CC BY-SA 4.0
<span class="int-own-work" lang="en">Own work</span>