diff --git a/LDDsimulation/UseCaseBase.py b/LDDsimulation/UseCaseBase.py
deleted file mode 100644
index 99d6b5336aa5a35bee6e51243cd70a588d3d62ff..0000000000000000000000000000000000000000
--- a/LDDsimulation/UseCaseBase.py
+++ /dev/null
@@ -1,19 +0,0 @@
-"""base class for LDD simulation use cases.
-
-This module defines a base class for the LDDsimulation usecases.
-"""
-
-import dolfin as df
-import mshr
-import numpy as np
-import sympy as sym
-import typing as tp
-import functools as ft
-import domainPatch as dp
-import LDDsimulation as ldd
-import helpers as hlp
-
-class UseCaseBase(object):
-    """Base class for LDD simulation use cases.
-    """
-    
diff --git a/LDDsimulation/unused_code.py b/LDDsimulation/unused_code.py
index 0e0b007091c73994b7eb9c68de572c11df06267a..c6ecc3300ec0a2e792610ca82f12c8b176d445ad 100644
--- a/LDDsimulation/unused_code.py
+++ b/LDDsimulation/unused_code.py
@@ -1,4 +1,25 @@
-# this was part of domainPatch.DomainPatch
+#!/bin/python3
+""" unused code that was retired in the LDDsimulation development.
+
+# LICENSE #####################################################################
+Copyright 2020, David Seus
+david.seus[at]ians.uni-stuttgart.de
+This file is part of the module LDDsimulation.
+
+    LDDsimulation is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    LDDsimulation is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with LDDsimulation.  If not, see <http://www.gnu.org/licenses/>.
+###############################################################################
+"""
 
 def calc_gravity_neumann_flux(self,
                   interface_index: int,