diff --git a/import2ledger/hooks/add_entity.py b/import2ledger/hooks/add_entity.py
index 000f966..ccf6ad9 100644
--- a/import2ledger/hooks/add_entity.py
+++ b/import2ledger/hooks/add_entity.py
@@ -5,6 +5,8 @@ class AddEntityHook:
     NAME_PREFIXES = frozenset([
         'da',
         'de',
+        'der',
+        'la',
         'van',
     ])
     NONASCII_RE = re.compile(r'[^-A-Za-z0-9]')