On 26 February 1814 King William I decreed that the Nederlands-Israëlitisch Seminarium (NIS) was to be established in Amsterdam to train rabbis, teachers and other officers serving the Jewish community.
Henri Workum, son of Salomon, attended the NIS.
In addition, a Jokos file (number 18296) on this family is at the Amsterdam Municipal Archive. Access is subject to authorization from the Stichting Joods Maatschappelijk Werk.