diff --git a/core/src/main/java/hudson/scm/browsers/ViewCVS.java b/core/src/main/java/hudson/scm/browsers/ViewCVS.java
index 07a53f181d5d1f4a8b7741d0e6eba56dbcb67c91..63e61c05aa036dfe19376fecc593ed31a5febe1e 100644
--- a/core/src/main/java/hudson/scm/browsers/ViewCVS.java
+++ b/core/src/main/java/hudson/scm/browsers/ViewCVS.java
@@ -16,6 +16,7 @@ import java.net.URL;
  * {@link RepositoryBrowser} for CVS.
  * @author Kohsuke Kawaguchi
  */
+// See http://viewvc.tigris.org/source/browse/*checkout*/viewvc/trunk/docs/url-reference.html
 public final class ViewCVS extends CVSRepositoryBrowser {
     /**
      * The URL of the top of the site.
diff --git a/core/src/main/java/hudson/scm/browsers/ViewSVN.java b/core/src/main/java/hudson/scm/browsers/ViewSVN.java
index 5512d9d6001b481304f2bcf275153763c27b4078..d5e27dbf02189f5d5390cd623e2cf5852f583c99 100644
--- a/core/src/main/java/hudson/scm/browsers/ViewSVN.java
+++ b/core/src/main/java/hudson/scm/browsers/ViewSVN.java
@@ -19,6 +19,7 @@ import java.net.URL;
  * @author Kohsuke Kawaguchi
  * @since 1.90
  */
+// See http://viewvc.tigris.org/source/browse/*checkout*/viewvc/trunk/docs/url-reference.html
 public class ViewSVN extends SubversionRepositoryBrowser {
     /**
      * The URL of the top of the site.