-<li><b>Groups of volumes</b> (<em>mandatory</em>): list of volume
- groups. These groups should be disjoint, i.e. should not have shared volumes.</li>
-<li> If <b>Create joint elements</b> option is activated, flat elements are created on the duplicated
-nodes: a triangular facet shared by two volumes of two groups generates
-a flat prism, a quadrangular facet generates a flat hexahedron.</li>
-<li> If <b>On all boundaries</b> : option is activated, the volumes, which are not
- included into <b>Groups of volumes</b>, are considered as another group and thus the nodes on the boundary between <b>Groups of volumes</b> and the remaining mesh are also duplicated.</li>
+ <li><b>Groups (faces or volumes) </b> (<em>mandatory</em>): list of mesh
+ groups. These groups should be disjoint, i.e. should not have shared
+ elements.</li>
+ <li> If <b>Create joint elements</b> option is activated, flat
+ elements are created on the duplicated nodes: a triangular facet
+ shared by two volumes of two groups generates a flat prism, a
+ quadrangular facet generates a flat hexahedron.
+ Correspondingly 2D joint elements (null area faces) are generated
+ where edges are shared by two faces.
+ <br>
+ The created flat volumes (or faces) are stored in groups. These groups are named
+ according to the position of the group in the list of groups: group
+ "j_n_p" is a group of flat elements that are built between the group \#n
+ and the group \#p in the group list. All flat elements are gathered
+ into the group named "joints3D" (correspondingly "joints2D"). The flat elements of multiple
+ junctions between the simple junction are stored in a group named
+ "jointsMultiples".</li>
+ <li> If <b>On all boundaries</b> option is activated, the volumes (or faces),
+ which are not included into <b>Groups</b> input, are considered
+ as another group and thus the nodes on the boundary
+ between <b>Groups</b> and the remaining mesh are also
+ duplicated.</li>