1st Internship of Teunis Jan Johannes van der Bunt1st Internship of Johannes L. Fr. van Hell3th Internship of Willem Marinus de Geest1st Internship of Bernhard Heinrich Kelder1st Internship of Johan Heukelom1st Internship of Hendrik van Ruyven1st Internship of Johanna P. van Ruyven1st Internship of Arie van Ruijven1st Internship of Frederik Wilhelm Taentzer1st Internship of Johan Voogt1st Internship of Gerardus Johannes Voogt1st Internship of Gerardus Bernardus Coersen