Lista regionu
- 1921 AA - Akersloot, Castricum, Noord-Holland
- 1921 AB - Akersloot, Castricum, Noord-Holland
- 1921 AC - Akersloot, Castricum, Noord-Holland
- 1921 AD - Akersloot, Castricum, Noord-Holland
- 1921 AE - Akersloot, Castricum, Noord-Holland
- 1921 AG - Akersloot, Castricum, Noord-Holland
- 1921 AH - Akersloot, Castricum, Noord-Holland
- 1921 AJ - Akersloot, Castricum, Noord-Holland
- 1921 AK - Akersloot, Castricum, Noord-Holland
- 1921 AL - Akersloot, Castricum, Noord-Holland
- 1921 AM - Akersloot, Castricum, Noord-Holland
- 1921 AN - Akersloot, Castricum, Noord-Holland
- 1921 AP - Akersloot, Castricum, Noord-Holland
- 1921 AR - Akersloot, Castricum, Noord-Holland
- 1921 AS - Akersloot, Castricum, Noord-Holland
- 1921 AT - Akersloot, Castricum, Noord-Holland
- 1921 AV - Akersloot, Castricum, Noord-Holland
- 1921 AW - Akersloot, Castricum, Noord-Holland
- 1921 AX - Akersloot, Castricum, Noord-Holland
- 1921 AZ - Akersloot, Castricum, Noord-Holland