diff --git a/nomad/normalizing/normalizer.py b/nomad/normalizing/normalizer.py
index db4b0df3eefd2894207a90001f37729302cad2a3..bbd76b3fd57082ecba4d54e816f900c7e6ba5b05 100644
--- a/nomad/normalizing/normalizer.py
+++ b/nomad/normalizing/normalizer.py
@@ -88,8 +88,11 @@ class SystemBasedNormalizer(Normalizer, metaclass=ABCMeta):
         pass
 
     def __representative_system(self):
-        """Used to select a representative system for this entry."""
+        """Used to select a representative system for this entry.
 
+        Attempt to find a single section_system that is representative for the
+        entry. The selection depends on the type of calculation.
+        """
         system_idx = None
 
         # Try to find a frame sequence, only first found is considered
diff --git a/tests/test_normalizing.py b/tests/test_normalizing.py
index 44ce8261e856c9f35ea800206859a23cdbfc9cbd..a80aa868d04dc3b187a0b732b223f182cd13dfa1 100644
--- a/tests/test_normalizing.py
+++ b/tests/test_normalizing.py
@@ -262,7 +262,8 @@ def test_representative_systems(single_point, molecular_dynamics, geometry_optim
             scc = backend["section_single_configuration_calculation"][scc_idx]
             repr_system_idx = scc["single_configuration_calculation_to_system_ref"]
 
-        # Check that only the representative system has been marded as such
+        # Check that only the representative system has been labels with
+        # "is_representative"
         for i, system in enumerate(backend["section_system"]):
             if i == repr_system_idx:
                 assert system["is_representative"] is True