The information on registered seafarers is not in all cases complete. As new sources are studied, information on engagements and medals etc. will be added to some of the already registered seafarers.
Londonregisteret:
Registernummer under krigen: London 11364 og 51269, NY 20815.
Ifølge London-kort var Blumberg registrert i mannskapsliste til «Tarifa» 30.4.1942 og 30.5.1942.
RA/S-2081/F/Fe/Fea/L0013