<item name="Editing groups" url="files/editing_groups.htm" />\r
<item name="Using operations on groups" url="files/using_operations_on_groups.htm" />\r
<item name="Constructing groups of specific elements" url="files/constructing_groups_of_specific_elements.htm" />\r
+ <item name="Deleting Groups" url="deleting_groups.htm" />\r
<item name="Selection filter library" url="selection_filter_library.htm" />\r
</book>\r
<book name="Modifying meshes" >\r
