Tweak Javadoc spelling
diff --git a/src/main/java/org/apache/commons/cli/Options.java b/src/main/java/org/apache/commons/cli/Options.java
index 1d02220..00fa414 100644
--- a/src/main/java/org/apache/commons/cli/Options.java
+++ b/src/main/java/org/apache/commons/cli/Options.java
@@ -120,7 +120,7 @@
      * </p>
      *
      * @param opt Short single-character name of the option.
-     * @param hasArg flag signally if an argument is required after this option
+     * @param hasArg flag signalling if an argument is required after this option
      * @param description Self-documenting description
      * @return the resulting Options instance
      */
@@ -139,7 +139,7 @@
      *
      * @param opt Short single-character name of the option.
      * @param longOpt Long multi-character name of the option.
-     * @param hasArg flag signally if an argument is required after this option
+     * @param hasArg flag signalling if an argument is required after this option
      * @param description Self-documenting description
      * @return the resulting Options instance
      */
@@ -166,7 +166,7 @@
      *
      * @param opt Short single-character name of the option.
      * @param longOpt Long multi-character name of the option.
-     * @param hasArg flag signally if an argument is required after this option
+     * @param hasArg flag signalling if an argument is required after this option
      * @param description Self-documenting description
      * @return the resulting Options instance
      * @since 1.4