North German Confederation Official stamp, issued in 1870, 2 Groschen, cancelled POSEN (Poznań, Poland) in 1870.
<a href="//commons.wikimedia.org/wiki/User:Jacquesverlaeken" title="User:Jacquesverlaeken">Jacquesverlaeken</a>
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<span class="int-own-work" lang="en">Own work</span>