Congress of Kraków
The participants - guests of the Polish king were Charles IV , Holy Roman Emperor , King Louis I of Hungary , King Valdemar IV of Denmark , King Peter I of Cyprus , Siemowit III of Masovia , Bolko II of Świdnica , Władysław Opolczyk , Rudolf IV , Duke of Austria , Bogislaw V , Duke of Pomerania , Casimir IV , Duke of Pomerania , Otto V , Duke of Bavaria and Louis VI the Roman . 
<triplet> Louis VI the Roman <subj> Otto V, Duke of Bavaria <obj> sibling