Except his brother Raphael, Louis had two other brothers and a sister who lived not anymore at home but elsewhere, who have been killed also during the Holocaust were Samuel, Abram Sija and Catharina.
City Archive of Amsterdam, archive card of Emanuel Zwartverwer .
In addition, a Jokos file (number 50038) on this family is at the Amsterdam Municipal Archive. Access is subject to authorization from the Stichting Joods Maatschappelijk Werk.