a masterpiece painting 
... that a masterpiece painting by Jan Matejko shows more than a dozen figures involved in the passing of the Polish-Lithuanian Constitution of May 3, 1791?
... that <b id="mwBG0"><a class="mw-redirect" href="./Constitution_of_May_3,_1791_(painting)" id="mwBG4" rel="mw:WikiLink" title="Constitution of May 3, 1791 (painting)">a masterpiece painting </a></b> <i id="mwBG8">(fragment pictured)</i> by <a href="./Jan_Matejko" id="mwBHA" rel="mw:WikiLink" title="Jan Matejko">Jan Matejko</a> shows more than a dozen figures involved in the passing of the <a href="./Polish–Lithuanian_Commonwealth" id="mwBHE" rel="mw:WikiLink" title="Polish–Lithuanian Commonwealth">Polish-Lithuanian</a> <a class="mw-redirect" href="./Constitution_of_May_3,_1791" id="mwBHI" rel="mw:WikiLink" title="Constitution of May 3, 1791">Constitution of May 3, 1791</a>?