diff --git a/features/communication.py b/features/communication.py
index b41e068..87594fb 100644
--- a/features/communication.py
+++ b/features/communication.py
@@ -8,6 +8,21 @@ from setup import db_engine, session
 call_types = {1: "incoming", 2: "outgoing", 3: "missed"}
 sms_types = {1: "received", 2: "sent"}
 
+FEATURES_CALLS = (
+    ["no_calls_all"]
+    + ["no_" + call_type for call_type in call_types.values()]
+    + ["duration_total_" + call_types.get(1), "duration_total_" + call_types.get(2)]
+    + ["duration_max_" + call_types.get(1), "duration_max_" + call_types.get(2)]
+    + ["no_" + call_types.get(1) + "_ratio", "no_" + call_types.get(2) + "_ratio"]
+    + ["no_contacts"]
+)
+
+# FEATURES_CALLS = ["no_all",
+# "no_incoming", "no_outgoing", "no_missed",
+# "duration_total_incoming", "duration_total_outgoing",
+# "duration_max_incoming", "duration_max_outgoing",
+# "no_incoming_ratio", "no_outgoing_ratio"]
+
 
 def get_call_data(usernames: Collection) -> pd.DataFrame:
     """
@@ -203,7 +218,7 @@ def contact_features(comm_df: pd.DataFrame) -> pd.DataFrame:
 
     Parameters
     ----------
-    df_enumerated: pd.DataFrame
+    comm_df: pd.DataFrame
         A dataframe of calls or SMSes.
 
     Returns
@@ -216,7 +231,7 @@ def contact_features(comm_df: pd.DataFrame) -> pd.DataFrame:
         df_enumerated.groupby(["participant_id", "contact_id"]).size().reset_index()
     )
     # Check whether df contains calls or SMS data since some
-    # features we want to calculate are type-specyfic
+    # features we want to calculate are type-specific
     if "call_duration" in df_enumerated:
         # Add a column with the total duration of calls between two people
         duration_count = (