As a son of Jonas van Loggem and Saartje Walg, Hartog had eight siblings, of whom one has survived the war. His other siblings , who also have been killed during the Holocaust were Rebecca, Jacob, Levie, Joseph, Rozette, Samuel and Max.
City Archive of Amsterdam, family registration card of Jonas van Loggem and website www.wiewaswie.nl.

In addition, a Jokos file (number 33448) on this household is at the Amsterdam Municipal Archive. Access is subject to authorization from the Stichting Joods Maatschappelijk Werk.

On 22 and 23 Febuary 1941, raids took place in Amsterdam,  in which 390 Jewish men were arrested and deported. Only two of them survived. A recent investigation has shown that more than 100 men were gassed in Hartheim Castle, while Mauthausen was established as the official place of death.

In February 2021, the City Archive of Amsterdam opened the exhibition “The raids of 22 and 23 February 1941 i…