diff --git a/src/java/org/apache/poi/ss/usermodel/CellStyle.java b/src/java/org/apache/poi/ss/usermodel/CellStyle.java
index d16619c4d8..80ce6e8c97 100644
--- a/src/java/org/apache/poi/ss/usermodel/CellStyle.java
+++ b/src/java/org/apache/poi/ss/usermodel/CellStyle.java
@@ -338,14 +338,14 @@ public interface CellStyle {
     short getIndex();
 
     /**
-     * set the data format (must be a valid format)
+     * set the data format (must be a valid format). Built in formats are defined at {@link BuiltinFormats}.
      * @see DataFormat
      */
 
     void setDataFormat(short fmt);
 
     /**
-     * get the index of the format
+     * get the index of the data format. Built in formats are defined at {@link BuiltinFormats}.
      * @see DataFormat
      */
     short getDataFormat();