diff --git a/NativeLand/Exceptions/NoBinaryForPlatformException.cs b/NativeLand/Exceptions/NoBinaryForPlatformException.cs
index 33aec0e..ff99f3c 100644
--- a/NativeLand/Exceptions/NoBinaryForPlatformException.cs
+++ b/NativeLand/Exceptions/NoBinaryForPlatformException.cs
@@ -1,3 +1,22 @@
+//
+// NativeLand  Copyright (C) 2023-2024  Aptivi
+//
+// This file is part of NativeLand
+//
+// NativeLand 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.
+//
+// NativeLand 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, see <https://www.gnu.org/licenses/>.
+//
+
 using System;
 
 namespace NativeLand.Exceptions
diff --git a/NativeLand/Exceptions/UnsupportedPlatformException.cs b/NativeLand/Exceptions/UnsupportedPlatformException.cs
index cb1e72a..4f75746 100644
--- a/NativeLand/Exceptions/UnsupportedPlatformException.cs
+++ b/NativeLand/Exceptions/UnsupportedPlatformException.cs
@@ -1,3 +1,22 @@
+//
+// NativeLand  Copyright (C) 2023-2024  Aptivi
+//
+// This file is part of NativeLand
+//
+// NativeLand 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.
+//
+// NativeLand 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, see <https://www.gnu.org/licenses/>.
+//
+
 using System;
 
 namespace NativeLand.Exceptions
diff --git a/NativeLand/LibraryFile.cs b/NativeLand/LibraryFile.cs
index 92321b9..640b91c 100644
--- a/NativeLand/LibraryFile.cs
+++ b/NativeLand/LibraryFile.cs
@@ -1,4 +1,23 @@
-namespace NativeLand
+//
+// NativeLand  Copyright (C) 2023-2024  Aptivi
+//
+// This file is part of NativeLand
+//
+// NativeLand 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.
+//
+// NativeLand 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, see <https://www.gnu.org/licenses/>.
+//
+
+namespace NativeLand
 {
 	/// <summary>
 	/// A class to store the information about native library file.
diff --git a/NativeLand/LibraryItem.cs b/NativeLand/LibraryItem.cs
index 6f23d47..47b17ea 100644
--- a/NativeLand/LibraryItem.cs
+++ b/NativeLand/LibraryItem.cs
@@ -1,3 +1,22 @@
+//
+// NativeLand  Copyright (C) 2023-2024  Aptivi
+//
+// This file is part of NativeLand
+//
+// NativeLand 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.
+//
+// NativeLand 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, see <https://www.gnu.org/licenses/>.
+//
+
 using NativeLand.Tools;
 using System;
 using System.Runtime.InteropServices;
diff --git a/NativeLand/LibraryItemInternal.cs b/NativeLand/LibraryItemInternal.cs
index 7298949..7d46211 100644
--- a/NativeLand/LibraryItemInternal.cs
+++ b/NativeLand/LibraryItemInternal.cs
@@ -1,3 +1,22 @@
+//
+// NativeLand  Copyright (C) 2023-2024  Aptivi
+//
+// This file is part of NativeLand
+//
+// NativeLand 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.
+//
+// NativeLand 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, see <https://www.gnu.org/licenses/>.
+//
+
 using System;
 using System.IO;
 using System.Runtime.InteropServices;
diff --git a/NativeLand/LibraryManager.cs b/NativeLand/LibraryManager.cs
index b70b2dc..1cb9b4b 100644
--- a/NativeLand/LibraryManager.cs
+++ b/NativeLand/LibraryManager.cs
@@ -1,4 +1,23 @@
-using System;
+//
+// NativeLand  Copyright (C) 2023-2024  Aptivi
+//
+// This file is part of NativeLand
+//
+// NativeLand 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.
+//
+// NativeLand 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, see <https://www.gnu.org/licenses/>.
+//
+
+using System;
 using System.IO;
 using System.Linq;
 using System.Runtime.InteropServices;
diff --git a/NativeLand/Properties/AssemblyAttributes.cs b/NativeLand/Properties/AssemblyAttributes.cs
index 7cec047..2227379 100644
--- a/NativeLand/Properties/AssemblyAttributes.cs
+++ b/NativeLand/Properties/AssemblyAttributes.cs
@@ -1,3 +1,22 @@
+//
+// NativeLand  Copyright (C) 2023-2024  Aptivi
+//
+// This file is part of NativeLand
+//
+// NativeLand 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.
+//
+// NativeLand 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, see <https://www.gnu.org/licenses/>.
+//
+
 using System.Runtime.CompilerServices;
 
 [assembly: InternalsVisibleTo("UnitTests, PublicKey=0024000004800000940000000602000000240000525341310004000001000100812e5231186da64504a543d5306da254e9062027fdaee10f569d93ecc1debc91770d1a077b762aea3ced57c09d9f033f9991960429980b625908628c80785a67a3b65bbb410c7623a0d7bbc1a9770b978358941714b5e2a806e5aa8fa58bb505f859be5fc3ebcce5b2c5d4c0820460c9d3e23cf66f3c00de5e0d154fec6a89b3")]
diff --git a/NativeLand/Tools/PathHelper.cs b/NativeLand/Tools/PathHelper.cs
index e029bf1..90e21ab 100644
--- a/NativeLand/Tools/PathHelper.cs
+++ b/NativeLand/Tools/PathHelper.cs
@@ -1,3 +1,22 @@
+//
+// NativeLand  Copyright (C) 2023-2024  Aptivi
+//
+// This file is part of NativeLand
+//
+// NativeLand 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.
+//
+// NativeLand 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, see <https://www.gnu.org/licenses/>.
+//
+
 using System;
 using System.IO;
 using System.Reflection;
diff --git a/NativeLand/Tools/Platform.cs b/NativeLand/Tools/Platform.cs
index d4158c6..0a96063 100644
--- a/NativeLand/Tools/Platform.cs
+++ b/NativeLand/Tools/Platform.cs
@@ -1,4 +1,23 @@
-namespace NativeLand.Tools
+//
+// NativeLand  Copyright (C) 2023-2024  Aptivi
+//
+// This file is part of NativeLand
+//
+// NativeLand 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.
+//
+// NativeLand 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, see <https://www.gnu.org/licenses/>.
+//
+
+namespace NativeLand.Tools
 {
     /// <summary>
     /// Platform (operating system).
diff --git a/NativeLand/Tools/ResourceAccessor.cs b/NativeLand/Tools/ResourceAccessor.cs
index 516c990..273e18a 100644
--- a/NativeLand/Tools/ResourceAccessor.cs
+++ b/NativeLand/Tools/ResourceAccessor.cs
@@ -1,3 +1,22 @@
+//
+// NativeLand  Copyright (C) 2023-2024  Aptivi
+//
+// This file is part of NativeLand
+//
+// NativeLand 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.
+//
+// NativeLand 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, see <https://www.gnu.org/licenses/>.
+//
+
 using System;
 using System.IO;
 using System.Reflection;
diff --git a/TestProcess/Program.cs b/TestProcess/Program.cs
index ffc0b3f..c834727 100644
--- a/TestProcess/Program.cs
+++ b/TestProcess/Program.cs
@@ -1,4 +1,23 @@
-using System;
+//
+// NativeLand  Copyright (C) 2023-2024  Aptivi
+//
+// This file is part of NativeLand
+//
+// NativeLand 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.
+//
+// NativeLand 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, see <https://www.gnu.org/licenses/>.
+//
+
+using System;
 using System.IO;
 using System.Reflection;
 using System.Runtime.InteropServices;