diff --git a/form_chooseactor.pas b/form_chooseactor.pas
index cf8a861..98c1d4e 100644
--- a/form_chooseactor.pas
+++ b/form_chooseactor.pas
@@ -1,3 +1,12 @@
+{
+  Stimulus Control
+  Copyright (C) 2014-2016 Carlos Rafael Fernandes Picanço, Universidade Federal do Pará.
+
+  The present file is distributed under the terms of the GNU General Public License (GPL v3.0).
+
+  You should have received a copy of the GNU General Public License
+  along with this program. If not, see <http://www.gnu.org/licenses/>.
+}
 unit form_chooseactor;
 
 {$mode objfpc}{$H+}
diff --git a/units/game_actors.pas b/units/game_actors.pas
index 4f60a25..dbfeea0 100644
--- a/units/game_actors.pas
+++ b/units/game_actors.pas
@@ -1,3 +1,12 @@
+{
+  Stimulus Control
+  Copyright (C) 2014-2016 Carlos Rafael Fernandes Picanço, Universidade Federal do Pará.
+
+  The present file is distributed under the terms of the GNU General Public License (GPL v3.0).
+
+  You should have received a copy of the GNU General Public License
+  along with this program. If not, see <http://www.gnu.org/licenses/>.
+}
 unit game_actors;
 
 {$mode objfpc}{$H+}
diff --git a/units/game_actors_point.pas b/units/game_actors_point.pas
index 4ddfb79..d516f24 100644
--- a/units/game_actors_point.pas
+++ b/units/game_actors_point.pas
@@ -1,3 +1,12 @@
+{
+  Stimulus Control
+  Copyright (C) 2014-2016 Carlos Rafael Fernandes Picanço, Universidade Federal do Pará.
+
+  The present file is distributed under the terms of the GNU General Public License (GPL v3.0).
+
+  You should have received a copy of the GNU General Public License
+  along with this program. If not, see <http://www.gnu.org/licenses/>.
+}
 unit game_actors_point;
 
 {$mode objfpc}{$H+}
diff --git a/units/game_control.pas b/units/game_control.pas
index e91e53c..349abf3 100644
--- a/units/game_control.pas
+++ b/units/game_control.pas
@@ -1,3 +1,12 @@
+{
+  Stimulus Control
+  Copyright (C) 2014-2016 Carlos Rafael Fernandes Picanço, Universidade Federal do Pará.
+
+  The present file is distributed under the terms of the GNU General Public License (GPL v3.0).
+
+  You should have received a copy of the GNU General Public License
+  along with this program. If not, see <http://www.gnu.org/licenses/>.
+}
 unit game_control;
 
 {$mode objfpc}{$H+}
@@ -378,6 +387,8 @@ begin
   FRowBase:=AValue;
 end;
 
+// many thanks to howardpc for this:
+// http://forum.lazarus.freepascal.org/index.php/topic,34559.msg227585.html#msg227585
 function TGameControl.AskQuestion(AQuestion: string): UTF8string;
 var
   Prompt: TForm;
diff --git a/units/game_experiment.pas b/units/game_experiment.pas
index ee08744..1679c73 100644
--- a/units/game_experiment.pas
+++ b/units/game_experiment.pas
@@ -1,3 +1,12 @@
+{
+  Stimulus Control
+  Copyright (C) 2014-2016 Carlos Rafael Fernandes Picanço, Universidade Federal do Pará.
+
+  The present file is distributed under the terms of the GNU General Public License (GPL v3.0).
+
+  You should have received a copy of the GNU General Public License
+  along with this program. If not, see <http://www.gnu.org/licenses/>.
+}
 unit game_experiment;
 
 {$mode objfpc}{$H+}
diff --git a/units/game_file_methods.pas b/units/game_file_methods.pas
index 268b058..79f2fe5 100644
--- a/units/game_file_methods.pas
+++ b/units/game_file_methods.pas
@@ -1,3 +1,12 @@
+{
+  Stimulus Control
+  Copyright (C) 2014-2016 Carlos Rafael Fernandes Picanço, Universidade Federal do Pará.
+
+  The present file is distributed under the terms of the GNU General Public License (GPL v3.0).
+
+  You should have received a copy of the GNU General Public License
+  along with this program. If not, see <http://www.gnu.org/licenses/>.
+}
 unit game_file_methods;
 
 {$mode objfpc}{$H+}
diff --git a/units/game_resources.pas b/units/game_resources.pas
index 0a9892c..94f0084 100644
--- a/units/game_resources.pas
+++ b/units/game_resources.pas
@@ -1,3 +1,12 @@
+{
+  Stimulus Control
+  Copyright (C) 2014-2016 Carlos Rafael Fernandes Picanço, Universidade Federal do Pará.
+
+  The present file is distributed under the terms of the GNU General Public License (GPL v3.0).
+
+  You should have received a copy of the GNU General Public License
+  along with this program. If not, see <http://www.gnu.org/licenses/>.
+}
 unit game_resources;
 
 {$mode objfpc}{$H+}
diff --git a/units/game_visual_elements.pas b/units/game_visual_elements.pas
index 86b4c33..839b282 100644
--- a/units/game_visual_elements.pas
+++ b/units/game_visual_elements.pas
@@ -1,3 +1,12 @@
+{
+  Stimulus Control
+  Copyright (C) 2014-2016 Carlos Rafael Fernandes Picanço, Universidade Federal do Pará.
+
+  The present file is distributed under the terms of the GNU General Public License (GPL v3.0).
+
+  You should have received a copy of the GNU General Public License
+  along with this program. If not, see <http://www.gnu.org/licenses/>.
+}
 unit game_visual_elements;
 
 {$mode objfpc}{$H+}
diff --git a/units/game_zmq_actors.pas b/units/game_zmq_actors.pas
index 7c7ccb2..9be9919 100644
--- a/units/game_zmq_actors.pas
+++ b/units/game_zmq_actors.pas
@@ -1,3 +1,12 @@
+{
+  Stimulus Control
+  Copyright (C) 2014-2016 Carlos Rafael Fernandes Picanço, Universidade Federal do Pará.
+
+  The present file is distributed under the terms of the GNU General Public License (GPL v3.0).
+
+  You should have received a copy of the GNU General Public License
+  along with this program. If not, see <http://www.gnu.org/licenses/>.
+}
 unit game_zmq_actors;
 
 {$mode objfpc}{$H+}
diff --git a/units/string_methods.pas b/units/string_methods.pas
index 158eabc..9994902 100644
--- a/units/string_methods.pas
+++ b/units/string_methods.pas
@@ -1,3 +1,12 @@
+{
+  Stimulus Control
+  Copyright (C) 2014-2016 Carlos Rafael Fernandes Picanço, Universidade Federal do Pará.
+
+  The present file is distributed under the terms of the GNU General Public License (GPL v3.0).
+
+  You should have received a copy of the GNU General Public License
+  along with this program. If not, see <http://www.gnu.org/licenses/>.
+}
 unit string_methods;
 
 {$mode objfpc}{$H+}
--
libgit2 0.21.2