diff --git a/gdsparse.c b/gdsparse.c
index 610cd11..a2115f4 100644
--- a/gdsparse.c
+++ b/gdsparse.c
@@ -5,8 +5,8 @@
  * This file is part of GDSII-Converter.
  *
  * GDSII-Converter 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.
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
  *
  * GDSII-Converter is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
diff --git a/gdsparse.h b/gdsparse.h
index cf55c73..ca16c07 100644
--- a/gdsparse.h
+++ b/gdsparse.h
@@ -5,8 +5,8 @@
  * This file is part of GDSII-Converter.
  *
  * GDSII-Converter 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.
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
  *
  * GDSII-Converter is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
diff --git a/layer-element.c b/layer-element.c
index 45d7aea..38a3530 100644
--- a/layer-element.c
+++ b/layer-element.c
@@ -5,8 +5,8 @@
  * This file is part of GDSII-Converter.
  *
  * GDSII-Converter 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.
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
  *
  * GDSII-Converter is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
diff --git a/layer-element.h b/layer-element.h
index ef13108..56de010 100644
--- a/layer-element.h
+++ b/layer-element.h
@@ -5,8 +5,8 @@
  * This file is part of GDSII-Converter.
  *
  * GDSII-Converter 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.
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
  *
  * GDSII-Converter is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
diff --git a/layer-selector.c b/layer-selector.c
index 32b8845..8eb2875 100644
--- a/layer-selector.c
+++ b/layer-selector.c
@@ -5,8 +5,8 @@
  * This file is part of GDSII-Converter.
  *
  * GDSII-Converter 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.
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
  *
  * GDSII-Converter is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
diff --git a/layer-selector.h b/layer-selector.h
index 008810e..4e9eb79 100644
--- a/layer-selector.h
+++ b/layer-selector.h
@@ -5,8 +5,8 @@
  * This file is part of GDSII-Converter.
  *
  * GDSII-Converter 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.
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
  *
  * GDSII-Converter is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
diff --git a/main.c b/main.c
index 1950cab..ba9d6b8 100644
--- a/main.c
+++ b/main.c
@@ -5,8 +5,8 @@
  * This file is part of GDSII-Converter.
  *
  * GDSII-Converter 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.
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
  *
  * GDSII-Converter is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of