diff --git a/app/paint/gimpheal.c b/app/paint/gimpheal.c
index 625444fa5b..495d6b7d3b 100644
--- a/app/paint/gimpheal.c
+++ b/app/paint/gimpheal.c
@@ -427,8 +427,8 @@ gimp_heal_laplace_loop (gfloat *pixels,
 
 /* Original Algorithm Design:
  *
- * T. Georgiev, "Photoshop Healing Brush: a Tool for Seamless Cloning
- * http://www.tgeorgiev.net/Photoshop_Healing.pdf
+ * T. Georgiev, "Photoshop Healing Brush: a Tool for Seamless Cloning"
+ * See: https://developer.gimp.org/core/algorithm/healing/
  */
 static void
 gimp_heal (GeglBuffer          *src_buffer,
diff --git a/app/pdb/drawable-cmds.c b/app/pdb/drawable-cmds.c
index ded88a68c7..b8b3650d5a 100644
--- a/app/pdb/drawable-cmds.c
+++ b/app/pdb/drawable-cmds.c
@@ -2222,7 +2222,7 @@ register_drawable_procs (GimpPDB *pdb)
                                "gimp-drawable-foreground-extract");
   gimp_procedure_set_static_help (procedure,
                                   "Extract the foreground of a drawable using a given trimap.",
-                                  "Image Segmentation by Uniform Color Clustering, see https://www.inf.fu-berlin.de/inst/pubs/tr-b-05-07.pdf",
+                                  "This procedure extracts the foreground from @drawable using @mask as a trimap. Set white as foreground, black as background and uncertain pixels as any other value, for the tri-map.",
                                   NULL);
   gimp_procedure_set_static_attribution (procedure,
                                          "Gerald Friedland <fland@inf.fu-berlin.de>, Kristian Jantz <jantz@inf.fu-berlin.de>, Sven Neumann <sven@gimp.org>",
diff --git a/libgimp/gimpdrawable_pdb.c b/libgimp/gimpdrawable_pdb.c
index b9eb69e3f5..a5c1d39fc0 100644
--- a/libgimp/gimpdrawable_pdb.c
+++ b/libgimp/gimpdrawable_pdb.c
@@ -1223,8 +1223,9 @@ _gimp_drawable_sub_thumbnail (GimpDrawable  *drawable,
  *
  * Extract the foreground of a drawable using a given trimap.
  *
- * Image Segmentation by Uniform Color Clustering, see
- * https://www.inf.fu-berlin.de/inst/pubs/tr-b-05-07.pdf
+ * This procedure extracts the foreground from @drawable using @mask as
+ * a trimap. Set white as foreground, black as background and uncertain
+ * pixels as any other value, for the tri-map.
  *
  * Returns: TRUE on success.
  *
diff --git a/pdb/groups/drawable.pdb b/pdb/groups/drawable.pdb
index 8464fb4767..1a979aca5c 100644
--- a/pdb/groups/drawable.pdb
+++ b/pdb/groups/drawable.pdb
@@ -1201,8 +1201,9 @@ sub drawable_foreground_extract {
     $blurb = 'Extract the foreground of a drawable using a given trimap.';
 
     $help = <<'HELP';
-Image Segmentation by Uniform Color Clustering, see
-https://www.inf.fu-berlin.de/inst/pubs/tr-b-05-07.pdf
+This procedure extracts the foreground from @drawable using @mask as a trimap.
+Set white as foreground, black as background and uncertain pixels as
+any other value, for the tri-map.
 HELP
 
     $author    = 'Gerald Friedland <fland@inf.fu-berlin.de>, Kristian Jantz <jantz@inf.fu-berlin.de>, Sven Neumann <sven@gimp.org>';