In June 1944, the "Philips-Jews" were transported to Auschwitz-Birkenau, from where they would be sent to other camps to work for electronics companies.
The booklet (87 pages) was a bilingual edition of modern Hebrew poetry, with translations in Dutch.
In addition to standard entries, David also used the diary to write poetry.
On 2 June 1944, while the family was being transported to Auschwitz-Birkenau, David managed to throw a letter from the train, an excerpt of which read: : Lieve vrinden, we zijn nu dicht bij de grens.
Het is wel teleurstellend, maar we waren erop voorbereid en zijn vol vertrouwen.
The editor was Koker's best friend Karel van het Reve, a professor of Slavic languages and literature, who during the war collected and kept the smuggled diary pieces.
It has been translated into English and was published in 2012 under the title At the Edge of the Abyss: A Concentration Camp Diary, 1943-1944.
[5][6] Koker's Diary was in 2012 finalist for the Jewish Book Award in the Holocaust category.