diff --git a/doc/salome/gui/SMESH/images/hypo_quad_params_2.png b/doc/salome/gui/SMESH/images/hypo_quad_params_2.png
new file mode 100644
index 000000000..9f6fa251e
Binary files /dev/null and b/doc/salome/gui/SMESH/images/hypo_quad_params_2.png differ
diff --git a/doc/salome/gui/SMESH/images/hypo_quad_params_res_2.png b/doc/salome/gui/SMESH/images/hypo_quad_params_res_2.png
new file mode 100644
index 000000000..6dc37e298
Binary files /dev/null and b/doc/salome/gui/SMESH/images/hypo_quad_params_res_2.png differ
diff --git a/doc/salome/gui/SMESH/input/2d_meshing_hypo.doc b/doc/salome/gui/SMESH/input/2d_meshing_hypo.doc
index c912c568f..25692d202 100644
--- a/doc/salome/gui/SMESH/input/2d_meshing_hypo.doc
+++ b/doc/salome/gui/SMESH/input/2d_meshing_hypo.doc
@@ -52,6 +52,20 @@ used as a degenerated edge.
 
 \image html hypo_quad_params_res.png "The resulting mesh"
 
+This hypothesis can be also used to mesh face that represents a
+segment of the circular face. There is one limitaion of the <b>Quadrangle
+mapping</b> algorithm related to the selecting of the degenerated
+vertex for the faces which are built from the angle > 180 degrees (see
+next picture).
+
+\image html hypo_quad_params_2.png "A 3/4 part of circle face"
+
+Selection of the wrong vertex for the <b>Quadrangle parameters</b>
+hypothesis will lead to the wrong mesh generation. The picture below
+shows good (left) and bad (right) results of meshing.
+
+\image html hypo_quad_params_res_2.png "The resulting meshes"
+
 <br>
 \anchor quadrangle_preference_anchor
 <h2>Quadrangle Preference</h2>
diff --git a/doc/salome/gui/SMESH/input/about_hypo.doc b/doc/salome/gui/SMESH/input/about_hypo.doc
index 578823bd6..cc8f5fd52 100644
--- a/doc/salome/gui/SMESH/input/about_hypo.doc
+++ b/doc/salome/gui/SMESH/input/about_hypo.doc
@@ -28,6 +28,7 @@ them, you operate numerical values):
 <ul>
 <li>\ref max_element_area_anchor "Max Element Area"</li>
 <li>\ref length_from_edges_anchor "Length from Edges"</li>
+<li>\ref hypo_quad_params_anchor "Quadrangle Parameters"</li>
 <li>\ref quadrangle_preference_anchor "Quadrangle Preference"</li>
 <li>\ref triangle_preference_anchor "Triangle Preference"</li>
 </ul>
diff --git a/doc/salome/gui/SMESH/input/prism_3d_algo.doc b/doc/salome/gui/SMESH/input/prism_3d_algo.doc
index 837923ac1..5589ba3a7 100644
--- a/doc/salome/gui/SMESH/input/prism_3d_algo.doc
+++ b/doc/salome/gui/SMESH/input/prism_3d_algo.doc
@@ -4,9 +4,9 @@
 
 3D extrusion algorithm can be used for meshing prisms, i.e. <b>3D Shapes</b>
 defined by two opposing faces having the same number of vertices and
-edges and meshed using the \ref projection_algos_page "2D Projection"
-algorithm. These two faces should be connected by quadrangle "side"
-faces.
+edges and meshed using, for example,  the \ref projection_algos_page
+"2D Projection" algorithm. These two faces should be connected by
+quadrangle "side" faces.
 
 The opposing faces can be meshed with either quadrangles or triangles,
 while the side faces should be meshed with quadrangles only.
@@ -17,4 +17,8 @@ As you can see, the <b>3D extrusion</b> algorithm permits to build and to
 have in the same 3D mesh such elements as hexahedrons, prisms and
 polyhedrons.
 
-*/
\ No newline at end of file
+\note This algorithm works correctly only if the opposing faces have
+the same (or similar) meshing topography. Otherwise, 3D extrusion
+algorithm can fail to build mesh volumes.
+
+*/
diff --git a/src/SMESHGUI/SMESHGUI_Hypotheses.cxx b/src/SMESHGUI/SMESHGUI_Hypotheses.cxx
index 0f2e0032b..b0ced7bb6 100644
--- a/src/SMESHGUI/SMESHGUI_Hypotheses.cxx
+++ b/src/SMESHGUI/SMESHGUI_Hypotheses.cxx
@@ -540,7 +540,8 @@ QString SMESHGUI_GenericHypothesisCreator::helpPage() const
     aHelpFileName = "radial_quadrangle_1D2D_algo_page.html";
   else if ( aHypType == "SegmentLengthAroundVertex")
     aHelpFileName = "segments_around_vertex_algo_page.html";
-    
+  else if ( aHypType == "QuadrangleParams")
+    aHelpFileName = "a2d_meshing_hypo_page.html#hypo_quad_params_anchor";
   return aHelpFileName;
 }