21
May |  Austria | Christoph, Constantin, Josef, Julio |  Bulgaria | Elena, Konstantin, Kosta, Kostadin, Kostadinka, Lenko, Stoyan |  Croatia | Dubravka, Eugen, Kristofor |  Czechia | Monika |  Denmark | Helene |  Estonia | Kindel, Konstantin, Kostel, Tiino |  Finland | Konsta, Konstantin, Kosti |  France | Constantin |  Greece | Elena, Elene, Eleni, Konstantina, Konstantinos, Lena |  Hungary | Konstantin |  Italy | Vittorio |  Latvia | Ernestine, Ingmārs, Vinija |  Lithuania | Vaidivutis, Valentas, Vydmina |  Norway | Eli, Ellen, Helene |  Poland | Donat, Donata, Jan, Kryspin, Przecława, Pudens, Tymoteusz, Walenty, Wiktor, Wiktoriusz |  Romania | Constantin, Elena |  Slovakia | Zina |  Spain | Cristóbal, Virginia |  Sweden | Conny, Konstantin |
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