diff --git a/R_lib/kin_r_library.R b/R_lib/kin_r_library.R
index fe39533ef..abaf86004 100644
--- a/R_lib/kin_r_library.R
+++ b/R_lib/kin_r_library.R
@@ -1,3 +1,18 @@
+### Copyright (C) 2018-2021 Marco De Lucia (GFZ Potsdam)
+###
+### POET 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 2 of the License, or (at your option) any later
+### version.
+###
+### POET 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
+### this program; if not, write to the Free Software Foundation, Inc., 51
+### Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+
 ## Simple function to check file extension. It is needed to check if
 ## the GridFile is SUM (MUFITS format) or rds/RData
 FileExt <- function (x)
diff --git a/R_lib/kin_r_library_warnings.R b/R_lib/kin_r_library_warnings.R
index f7ad279b0..bc0374965 100644
--- a/R_lib/kin_r_library_warnings.R
+++ b/R_lib/kin_r_library_warnings.R
@@ -1,3 +1,18 @@
+### Copyright (C) 2018-2021 Marco De Lucia (GFZ Potsdam)
+###
+### POET 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 2 of the License, or (at your option) any later
+### version.
+###
+### POET 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
+### this program; if not, write to the Free Software Foundation, Inc., 51
+### Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+
 ## Simple function to check file extension. It is needed to check if
 ## the GridFile is SUM (MUFITS format) or rds/RData
 FileExt <- function (x)
diff --git a/R_lib/parallel_r_library.R b/R_lib/parallel_r_library.R
index 1b1f1c035..ecaecbcc5 100644
--- a/R_lib/parallel_r_library.R
+++ b/R_lib/parallel_r_library.R
@@ -1,3 +1,18 @@
+### Copyright (C) 2018-2021 Marco De Lucia (GFZ Potsdam)
+###
+### POET 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 2 of the License, or (at your option) any later
+### version.
+###
+### POET 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
+### this program; if not, write to the Free Software Foundation, Inc., 51
+### Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+
 distribute_work_packages <- function(len, package_size) 
 {
     ## Check if work_package is a divisor of grid length and act
diff --git a/src/DHT/DHT.c b/src/DHT/DHT.c
index 74f8b6220..b773cba06 100644
--- a/src/DHT/DHT.c
+++ b/src/DHT/DHT.c
@@ -1,3 +1,20 @@
+/*
+** Copyright (C) 2017-2021 Max Luebke (University of Potsdam)
+**
+** POET 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 2 of the License, or (at your option) any later
+** version.
+**
+** POET 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
+** this program; if not, write to the Free Software Foundation, Inc., 51
+** Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+*/
+
 #include "DHT.h"
 
 #include <inttypes.h>
diff --git a/src/DHT/DHT.h b/src/DHT/DHT.h
index 6fed3a79b..1acba5022 100644
--- a/src/DHT/DHT.h
+++ b/src/DHT/DHT.h
@@ -1,3 +1,20 @@
+/*
+** Copyright (C) 2017-2021 Max Luebke (University of Potsdam)
+**
+** POET 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 2 of the License, or (at your option) any later
+** version.
+**
+** POET 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
+** this program; if not, write to the Free Software Foundation, Inc., 51
+** Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+*/
+
 /**
  * @file DHT.h
  * @author Max Lübke (mluebke@uni-potsdam.de)
@@ -292,4 +309,4 @@ static void set_flag(char* flag_byte);
  */
 static int read_flag(char flag_byte);
 
-#endif /* DHT_H */
\ No newline at end of file
+#endif /* DHT_H */
diff --git a/src/DHT/DHT_Wrapper.cpp b/src/DHT/DHT_Wrapper.cpp
index e71caa679..d254717ed 100644
--- a/src/DHT/DHT_Wrapper.cpp
+++ b/src/DHT/DHT_Wrapper.cpp
@@ -1,3 +1,23 @@
+/*
+** Copyright (C) 2018-2021 Alexander Lindemann, Max Luebke (University of
+** Potsdam)
+**
+** Copyright (C) 2018-2021 Marco De Lucia (GFZ Potsdam)
+**
+** POET 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 2 of the License, or (at your option) any later
+** version.
+**
+** POET 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
+** this program; if not, write to the Free Software Foundation, Inc., 51
+** Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+*/
+
 #include "DHT_Wrapper.h"
 
 #include <math.h>
diff --git a/src/DHT/DHT_Wrapper.h b/src/DHT/DHT_Wrapper.h
index 2612e8e3c..dd7612f5e 100644
--- a/src/DHT/DHT_Wrapper.h
+++ b/src/DHT/DHT_Wrapper.h
@@ -1,3 +1,23 @@
+/*
+** Copyright (C) 2018-2021 Alexander Lindemann, Max Luebke (University of
+** Potsdam)
+**
+** Copyright (C) 2018-2021 Marco De Lucia (GFZ Potsdam)
+**
+** POET 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 2 of the License, or (at your option) any later
+** version.
+**
+** POET 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
+** this program; if not, write to the Free Software Foundation, Inc., 51
+** Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+*/
+
 #ifndef DHT_WRAPPER_H
 #define DHT_WRAPPER_H
 
diff --git a/src/model/ChemMaster.cpp b/src/model/ChemMaster.cpp
index 4c6e1c54a..afb0452e2 100644
--- a/src/model/ChemMaster.cpp
+++ b/src/model/ChemMaster.cpp
@@ -1,3 +1,23 @@
+/*
+** Copyright (C) 2018-2021 Alexander Lindemann, Max Luebke (University of
+** Potsdam)
+**
+** Copyright (C) 2018-2021 Marco De Lucia (GFZ Potsdam)
+**
+** POET 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 2 of the License, or (at your option) any later
+** version.
+**
+** POET 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
+** this program; if not, write to the Free Software Foundation, Inc., 51
+** Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+*/
+
 #include <Rcpp.h>
 
 #include <iostream>
diff --git a/src/model/ChemSim.cpp b/src/model/ChemSim.cpp
index 0e6f4c735..2b5a265ab 100644
--- a/src/model/ChemSim.cpp
+++ b/src/model/ChemSim.cpp
@@ -1,3 +1,23 @@
+/*
+** Copyright (C) 2018-2021 Alexander Lindemann, Max Luebke (University of
+** Potsdam)
+**
+** Copyright (C) 2018-2021 Marco De Lucia (GFZ Potsdam)
+**
+** POET 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 2 of the License, or (at your option) any later
+** version.
+**
+** POET 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
+** this program; if not, write to the Free Software Foundation, Inc., 51
+** Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+*/
+
 #include "ChemSim.h"
 
 #include <Rcpp.h>
diff --git a/src/model/ChemSim.h b/src/model/ChemSim.h
index 6d5105ae8..dc5fb12a4 100644
--- a/src/model/ChemSim.h
+++ b/src/model/ChemSim.h
@@ -1,3 +1,23 @@
+/*
+** Copyright (C) 2018-2021 Alexander Lindemann, Max Luebke (University of
+** Potsdam)
+**
+** Copyright (C) 2018-2021 Marco De Lucia (GFZ Potsdam)
+**
+** POET 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 2 of the License, or (at your option) any later
+** version.
+**
+** POET 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
+** this program; if not, write to the Free Software Foundation, Inc., 51
+** Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+*/
+
 #ifndef CHEMSIM_H
 #define CHEMSIM_H
 
diff --git a/src/model/ChemWorker.cpp b/src/model/ChemWorker.cpp
index e9d21899b..c2db69341 100644
--- a/src/model/ChemWorker.cpp
+++ b/src/model/ChemWorker.cpp
@@ -1,3 +1,23 @@
+/*
+** Copyright (C) 2018-2021 Alexander Lindemann, Max Luebke (University of
+** Potsdam)
+**
+** Copyright (C) 2018-2021 Marco De Lucia (GFZ Potsdam)
+**
+** POET 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 2 of the License, or (at your option) any later
+** version.
+**
+** POET 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
+** this program; if not, write to the Free Software Foundation, Inc., 51
+** Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+*/
+
 #include <Rcpp.h>
 
 #include <iostream>
diff --git a/src/model/Grid.cpp b/src/model/Grid.cpp
index b08e551e0..ec475e6af 100644
--- a/src/model/Grid.cpp
+++ b/src/model/Grid.cpp
@@ -1,3 +1,23 @@
+/*
+** Copyright (C) 2018-2021 Alexander Lindemann, Max Luebke (University of
+** Potsdam)
+**
+** Copyright (C) 2018-2021 Marco De Lucia (GFZ Potsdam)
+**
+** POET 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 2 of the License, or (at your option) any later
+** version.
+**
+** POET 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
+** this program; if not, write to the Free Software Foundation, Inc., 51
+** Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+*/
+
 #include "Grid.h"
 
 using namespace poet;
diff --git a/src/model/Grid.h b/src/model/Grid.h
index 898f1232a..75011f891 100644
--- a/src/model/Grid.h
+++ b/src/model/Grid.h
@@ -1,3 +1,23 @@
+/*
+** Copyright (C) 2018-2021 Alexander Lindemann, Max Luebke (University of
+** Potsdam)
+**
+** Copyright (C) 2018-2021 Marco De Lucia (GFZ Potsdam)
+**
+** POET 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 2 of the License, or (at your option) any later
+** version.
+**
+** POET 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
+** this program; if not, write to the Free Software Foundation, Inc., 51
+** Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+*/
+
 #ifndef GRID_H
 #define GRID_H
 
diff --git a/src/model/TransportSim.cpp b/src/model/TransportSim.cpp
index 739f04ffe..711820d14 100644
--- a/src/model/TransportSim.cpp
+++ b/src/model/TransportSim.cpp
@@ -1,3 +1,23 @@
+/*
+** Copyright (C) 2018-2021 Alexander Lindemann, Max Luebke (University of
+** Potsdam)
+**
+** Copyright (C) 2018-2021 Marco De Lucia (GFZ Potsdam)
+**
+** POET 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 2 of the License, or (at your option) any later
+** version.
+**
+** POET 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
+** this program; if not, write to the Free Software Foundation, Inc., 51
+** Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+*/
+
 #include "TransportSim.h"
 
 #include <mpi.h>
diff --git a/src/model/TransportSim.h b/src/model/TransportSim.h
index c2cd8880a..f5bc9b0bf 100644
--- a/src/model/TransportSim.h
+++ b/src/model/TransportSim.h
@@ -1,3 +1,23 @@
+/*
+** Copyright (C) 2018-2021 Alexander Lindemann, Max Luebke (University of
+** Potsdam)
+**
+** Copyright (C) 2018-2021 Marco De Lucia (GFZ Potsdam)
+**
+** POET 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 2 of the License, or (at your option) any later
+** version.
+**
+** POET 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
+** this program; if not, write to the Free Software Foundation, Inc., 51
+** Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+*/
+
 #ifndef TRANSPORT_SIM_H
 #define TRANSPORT_SIM_H
 
@@ -59,4 +79,4 @@ class TransportSim {
 };
 }  // namespace poet
 
-#endif  // TRANSPORT_SIM_H
\ No newline at end of file
+#endif  // TRANSPORT_SIM_H
diff --git a/src/poet.cpp b/src/poet.cpp
index 20e17bc7b..5ed95302c 100644
--- a/src/poet.cpp
+++ b/src/poet.cpp
@@ -1,3 +1,23 @@
+/*
+** Copyright (C) 2018-2021 Alexander Lindemann, Max Luebke (University of
+** Potsdam)
+**
+** Copyright (C) 2018-2021 Marco De Lucia (GFZ Potsdam)
+**
+** POET 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 2 of the License, or (at your option) any later
+** version.
+**
+** POET 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
+** this program; if not, write to the Free Software Foundation, Inc., 51
+** Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+*/
+
 #include <ChemSim.h>
 #include <Grid.h>
 #include <RRuntime.h>
diff --git a/src/util/RRuntime.cpp b/src/util/RRuntime.cpp
index 7ac939292..fccf8726b 100644
--- a/src/util/RRuntime.cpp
+++ b/src/util/RRuntime.cpp
@@ -1,3 +1,23 @@
+/*
+** Copyright (C) 2018-2021 Alexander Lindemann, Max Luebke (University of
+** Potsdam)
+**
+** Copyright (C) 2018-2021 Marco De Lucia (GFZ Potsdam)
+**
+** POET 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 2 of the License, or (at your option) any later
+** version.
+**
+** POET 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
+** this program; if not, write to the Free Software Foundation, Inc., 51
+** Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+*/
+
 #include "RRuntime.h"
 
 #include <RInside.h>
diff --git a/src/util/RRuntime.h b/src/util/RRuntime.h
index 89652f7dd..f09933a72 100644
--- a/src/util/RRuntime.h
+++ b/src/util/RRuntime.h
@@ -1,3 +1,23 @@
+/*
+** Copyright (C) 2018-2021 Alexander Lindemann, Max Luebke (University of
+** Potsdam)
+**
+** Copyright (C) 2018-2021 Marco De Lucia (GFZ Potsdam)
+**
+** POET 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 2 of the License, or (at your option) any later
+** version.
+**
+** POET 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
+** this program; if not, write to the Free Software Foundation, Inc., 51
+** Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+*/
+
 #ifndef RRUNTIME_H
 #define RRUNTIME_H
 
diff --git a/src/util/SimParams.cpp b/src/util/SimParams.cpp
index d97734354..623a298db 100644
--- a/src/util/SimParams.cpp
+++ b/src/util/SimParams.cpp
@@ -1,3 +1,23 @@
+/*
+** Copyright (C) 2018-2021 Alexander Lindemann, Max Luebke (University of
+** Potsdam)
+**
+** Copyright (C) 2018-2021 Marco De Lucia (GFZ Potsdam)
+**
+** POET 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 2 of the License, or (at your option) any later
+** version.
+**
+** POET 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
+** this program; if not, write to the Free Software Foundation, Inc., 51
+** Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+*/
+
 #include "SimParams.h"
 
 #include <Rcpp.h>
diff --git a/src/util/SimParams.h b/src/util/SimParams.h
index 494833bb2..86de2d710 100644
--- a/src/util/SimParams.h
+++ b/src/util/SimParams.h
@@ -1,3 +1,23 @@
+/*
+** Copyright (C) 2018-2021 Alexander Lindemann, Max Luebke (University of
+** Potsdam)
+**
+** Copyright (C) 2018-2021 Marco De Lucia (GFZ Potsdam)
+**
+** POET 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 2 of the License, or (at your option) any later
+** version.
+**
+** POET 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
+** this program; if not, write to the Free Software Foundation, Inc., 51
+** Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+*/
+
 #ifndef PARSER_H
 #define PARSER_H
 
@@ -251,4 +271,4 @@ class SimParams {
   std::string out_dir;
 };
 }  // namespace poet
-#endif  // PARSER_H
\ No newline at end of file
+#endif  // PARSER_H