Remove `dom/lgm/`.

doc/HOWTO

@@ -152,17 +152,6 @@ A: Saving data without the multigrid is done by using the option '$p' in the
         loaddata test $t xdr $a sol $r;
 
 
-UG/ug/dom/lgm:
--------------
-
-Q: How is the left/right subdomain information of 3d-lgm surface defined?
-
-A: The right hand rule applies in the following way: Consider
-  the nodes of the first triangle. If you follow the rotation direction
-  of nodes 0, 1 and 2 the thumb of your right hand points into the 
-  left subdomain. 
-
-
 UG/ug/arch:
 --------