1st Internship of Arie Franciscus van Dijk1st Internship of Hendricus C. Dix1st Internship of Jan Hessels3th Internship of Jan Hessels2nd Internship of Jan Michaël Augustin1st Internship of Frederik Wilhelm Meyer1st Internship of Cornelis Wilhelmus Koestal1st Internship of Johannes Pieter Jacobus Plas1st Internship of Hendricus C J van Schouten3th Internship of Willem Vonk1st Internship of Johannes Visser