diff --git a/pySim/ts_51_011.py b/pySim/ts_51_011.py
index 70c38b18..e5ffdd4c 100644
--- a/pySim/ts_51_011.py
+++ b/pySim/ts_51_011.py
@@ -1117,8 +1117,8 @@ class DF_GSM(CardDF):
             EF_MBI(),
             EF_MWIS(),
             EF_CFIS(),
-            EF_EXT('6fc8', None, 'EF.EXT6', desc='Externsion6 (MBDN)'),
-            EF_EXT('6fcc', None, 'EF.EXT7', desc='Externsion7 (CFIS)'),
+            EF_EXT('6fc8', None, 'EF.EXT6', desc='Extension6 (MBDN)'),
+            EF_EXT('6fcc', None, 'EF.EXT7', desc='Extension7 (CFIS)'),
             EF_SPDI(),
             EF_MMSN(),
             EF_EXT('6fcf', None, 'EF.EXT8', desc='Extension8 (MMSN)'),