Portrait of Lev Shestov (1866-1938) signed 'Boris/Grigoriew' (upper left)
<bdi><a href="https://en.wikipedia.org/wiki/en:Boris_Grigoriev" class="extiw" title="w:en:Boris Grigoriev"><span title="Russian artist (1886-1939)">Boris Grigoriev</span></a>
</bdi>
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