Upper-left corner: sender address
<p>Top centre: mention of "cécogramme" (cecogram)
Upper-right corner: international cecogram label
Left: mention of "par avion" (airmail)
</p>
Lower-right corner: recipient address
<a href="//commons.wikimedia.org/w/index.php?title=User:Illinois347&amp;action=edit&amp;redlink=1" class="new" title="User:Illinois347 (page does not exist)">Illinois347</a>
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<span class="int-own-work" lang="en">Own work</span>