Alfred David Henri Blok was a son of Jaob Blok and Mietje Zon. He married 22 Juni 1939 in Amsterdam the widow of Arnold Machol, Karolina Füllenbaum, a daughter of Simon Füllenbaum and Flora Delmonte.
Cityh Archive of Amsterdam, archive cards of Alfred David Henri Blok and Karolina Füllenbaum.