diff --git a/README.md b/README.md
index cef20a5bc75eb48a494148946e1c6f438e2b86c6..4ccf9edc9e112981e3cd778330d6c938b046bc84 100644
--- a/README.md
+++ b/README.md
@@ -10,4 +10,17 @@ The current implementation offers a set of elementary tests to check that the or
 
 # License
 
-This project is distributed under the terms of the *GNU General Public License V3.0 or later* (GPL-3.0-or-later). Check the contents of the *COPYING* file for further details.
\ No newline at end of file
+   Copyright 2004 INAF - Osservatorio Astronomico di Cagliari
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+   
\ No newline at end of file
diff --git a/build/README.md b/build/README.md
index bd4fe07fd2a7db8b7b645a23a001180531071154..ecf636b9aea41b095585926be28304281b58c8e2 100644
--- a/build/README.md
+++ b/build/README.md
@@ -1,5 +1,3 @@
-Distributed under the terms of *GNU GPL-3.0-or-later*
-
 # Folder instructions
 
 This directory collects all the output of make builds.
@@ -97,3 +95,20 @@ This program checks for the consistency of transition matrix data files. It is e
 > ./test_TTMS PATH_TO_c_TTMS PATH_TO_c_TTMS.hd5
 
 where the arguments must be valid paths to binary transition matrix files saved in the legaci or the _HDF5_ format. Similarly to the previous case, the program writes a short log and returns a result value of 0, for success, or a positive number in case of inconsistency detection.
+
+# License
+
+   Copyright 2004 INAF - Osservatorio Astronomico di Cagliari
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+   
diff --git a/containers/docker/README.md b/containers/docker/README.md
index 555a487d89a97d85acd42a412e535e3ba6e383ff..13b5bf1433a0b954b2ed7be883dd7bbe326306a7 100644
--- a/containers/docker/README.md
+++ b/containers/docker/README.md
@@ -1,5 +1,3 @@
-Distributed under the terms of *GNU GPL-3.0-or-later*
-
 # Docker support for the NP-TMcode project
 
 This Dockerfile allows to create mainly:
@@ -11,4 +9,21 @@ In order for the docker build to correctly set the context, so that it can acces
 
    > docker build -f Dockerfile ../.. --target \<image name\>
 
-where `<image name>` is either `np-tmcode` or `np-tmcode-run`. One may also add the docker build option `-t tagname` to specify the `tagname` the built image should have in his/her registry.
\ No newline at end of file
+where `<image name>` is either `np-tmcode` or `np-tmcode-run`. One may also add the docker build option `-t tagname` to specify the `tagname` the built image should have in his/her registry.
+
+# License
+
+   Copyright 2004 INAF - Osservatorio Astronomico di Cagliari
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+   
diff --git a/containers/singularity/README.md b/containers/singularity/README.md
index 20e9767c4df0e96126e41ef74e1b3b4b941dda42..086c40dcabefff1f021c6e6cc7de8d3835275b8b 100644
--- a/containers/singularity/README.md
+++ b/containers/singularity/README.md
@@ -1,5 +1,3 @@
-Distributed under the terms of *GNU GPL-3.0-or-later*
-
 # Singularity support for the NP-TMcode project
 
 This `np-tmcode-run.def` file allows to create a np-tmcode-run image, that contains only the pre-built executables, python test scripts, compiled documentation, and the minimal runtime to run them
@@ -18,4 +16,21 @@ or directly as
 
    > \<full path to image name\> \<np-tmcode command\>
 
-where `<full path to image name>` is the name of the sif image, including full or relative path to it, and `<np-tmcode command>` is one of the executables built in np-tmcode project, or the `pycompare.py` script used to compare results between the Fortran and C++ versions of the code. These executables, as well as the minimum runtime for them to execute correctly, are embedded in the image, and "see" the current directory the image is run in (which technically is automatically bind-mounted by singularity in the running image instance).
\ No newline at end of file
+where `<full path to image name>` is the name of the sif image, including full or relative path to it, and `<np-tmcode command>` is one of the executables built in np-tmcode project, or the `pycompare.py` script used to compare results between the Fortran and C++ versions of the code. These executables, as well as the minimum runtime for them to execute correctly, are embedded in the image, and "see" the current directory the image is run in (which technically is automatically bind-mounted by singularity in the running image instance).
+
+# License
+
+   Copyright 2004 INAF - Osservatorio Astronomico di Cagliari
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+   
diff --git a/doc/src/README.md b/doc/src/README.md
index 40ca9e988adb0865d58cb2011fb40b4bda0e3244..dec0e441bc3a292243cfa574a6cd77ed4bdde426 100644
--- a/doc/src/README.md
+++ b/doc/src/README.md
@@ -1,5 +1,3 @@
-Distributed under the terms of *GNU GPL-3.0-or-later*
-
 # Folder instructions
 
 This directory contains the material to build the project documentation with *doxygen*.
@@ -14,4 +12,21 @@ Alternatively, you can use `make` from the project `src` folder (named `np_tmcod
 
 > make docs
 
-*doxygen* will automatically build the HTML structure to cover all the documented source code and it will additionally provide the fundamental structure to prepare a LaTeX formatted version of the documents. These two outputs will be placed, respectively, under the folders `np_tmcode/doc/build/html` and `np_tmcode/doc/build/latex`.
\ No newline at end of file
+*doxygen* will automatically build the HTML structure to cover all the documented source code and it will additionally provide the fundamental structure to prepare a LaTeX formatted version of the documents. These two outputs will be placed, respectively, under the folders `np_tmcode/doc/build/html` and `np_tmcode/doc/build/latex`.
+
+# License
+
+   Copyright 2004 INAF - Osservatorio Astronomico di Cagliari
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+