Source: Yad Vashem
Willem Roco had agreed with his good school-days friend, Wilhelm (Wim) Gieben, both living in Rotterdam, that the latter would try and take care of the Roco children, Annette, b.1938, and Emile, b.1933, in the event that the Roco family would be ordered for “work in the East” - …
In addition, a Jokos file (number 3892) on this family is at the Amsterdam Municipal Archive. Access is subject to authorization from the Stichting Joods Maatschappelijk Werk.