Calm Sea by Gustave Courbet, 1866, oil on canvas - National Gallery of Art, Washington, DC, USA. This painting is in the public domain because the artist died more than 70 years ago.
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<a href="//commons.wikimedia.org/wiki/User:Daderot" title="User:Daderot">Daderot</a></div>
<span class="int-own-work" lang="en">Own work</span>