diff --git a/owlapy/owl_literal.py b/owlapy/owl_literal.py
index 25b17dee..43d77ec4 100644
--- a/owlapy/owl_literal.py
+++ b/owlapy/owl_literal.py
@@ -741,7 +741,7 @@ def __init__(self, value, type_=None):
             value = time.fromisoformat(value) if isinstance(value, str) else value
         if isinstance(value, Timedelta) or type_ is DurationOWLDatatype:
             value = Timedelta(value) if isinstance(value, str) else value
-        assert type(value) is [datetime, date, time, Timedelta]
+        assert type(value) in [datetime, date, time, Timedelta]
         self._v = value
         self._type = type_