diff --git a/advlabdb/advlabdb_independent_funs.py b/advlabdb/advlabdb_independent_funs.py
index 668c61b..83d0ddb 100644
--- a/advlabdb/advlabdb_independent_funs.py
+++ b/advlabdb/advlabdb_independent_funs.py
@@ -37,18 +37,28 @@ def missing_formatter(view, context, model, name):
 
 def str_without_semester_formatter(view, context, model, name):
     attr = deep_getattr(model, name)
-    if attr is not None:
-        return attr.str_without_semester()
 
-    return attr
+    if attr is None:
+        return ""
+
+    if hasattr(attr, "__iter__") and not isinstance(attr, str):
+        # List of attributes
+        return ", ".join([a.str_without_semester() for a in attr])
+
+    return attr.str_without_semester()
 
 
 def str_formatter(view, context, model, name):
     attr = deep_getattr(model, name)
-    if attr is not None:
-        return attr.str()
 
-    return attr
+    if attr is None:
+        return ""
+
+    if hasattr(attr, "__iter__") and not isinstance(attr, str):
+        # List of attributes
+        return ", ".join([a.str() for a in attr])
+
+    return attr.str()
 
 
 def _details_link(url, attr, attr_formatter):