diff --git a/documentation/user-guide-basics/analyze-telephone-number.dmn b/documentation/user-guide-basics/analyze-telephone-number.dmn
index eeea7b71..1b77cbe3 100644
--- a/documentation/user-guide-basics/analyze-telephone-number.dmn
+++ b/documentation/user-guide-basics/analyze-telephone-number.dmn
@@ -13,7 +13,7 @@
         </inputExpression>
       </input>
       <output id="output_1" label="The Real Chuck Norris?" name="isRealChuckNorris" typeRef="boolean" biodi:width="213" />
-      <output id="OutputClause_1673dq5" label="Which Number?" name="which_number" typeRef="string" />
+      <output id="OutputClause_1673dq5" label="Which Number?" name="whichNumber" typeRef="string" />
       <rule id="DecisionRule_1yjspgz">
         <description>Chuck's Fan Club Number</description>
         <inputEntry id="UnaryTests_085sq4v">