diff --git a/src/printer/prt_cpmap.c b/src/printer/prt_cpmap.c
index 62c00d544..f5da0e91d 100644
--- a/src/printer/prt_cpmap.c
+++ b/src/printer/prt_cpmap.c
@@ -10,12 +10,12 @@
  *
  *
  *
- * Authors:	Michael Dr�ing, <michael@drueing.de>
+ * Authors:	Michael Drüing, <michael@drueing.de>
  *		Fred N. van Kempen, <decwiz@yahoo.com>
  *
  *		Based on code by Frederic Weymann (originally for DosBox.)
  *
- *		Copyright 2018 Michael Dr�ing.
+ *		Copyright 2018 Michael Drüing.
  *		Copyright 2018 Fred N. van Kempen.
  *
  *		Redistribution and  use  in source  and binary forms, with
diff --git a/src/printer/prt_escp.c b/src/printer/prt_escp.c
index 8e490e9e1..22bd86e06 100644
--- a/src/printer/prt_escp.c
+++ b/src/printer/prt_escp.c
@@ -10,12 +10,12 @@
  *
  *
  *
- * Authors:	Michael Dr�ing, <michael@drueing.de>
+ * Authors:	Michael Drüing, <michael@drueing.de>
  *		Fred N. van Kempen, <decwiz@yahoo.com>
  *
  *		Based on code by Frederic Weymann (originally for DosBox.)
  *
- *		Copyright 2018,2019 Michael Dr�ing.
+ *		Copyright 2018,2019 Michael Drüing.
  *		Copyright 2019,2019 Fred N. van Kempen.
  *
  *		Redistribution and  use  in source  and binary forms, with
diff --git a/src/qt/qt_sdl.c b/src/qt/qt_sdl.c
index 81a1311d1..08f240862 100644
--- a/src/qt/qt_sdl.c
+++ b/src/qt/qt_sdl.c
@@ -15,10 +15,10 @@
  *
  *
  * Authors:	Fred N. van Kempen, <decwiz@yahoo.com>
- *		Michael Dr�ing, <michael@drueing.de>
+ *		Michael Drüing, <michael@drueing.de>
  *
  *		Copyright 2018-2020 Fred N. van Kempen.
- *		Copyright 2018-2020 Michael Dr�ing.
+ *		Copyright 2018-2020 Michael Drüing.
  *
  *		Redistribution and  use  in source  and binary forms, with
  *		or  without modification, are permitted  provided that the
diff --git a/src/win/win_sdl.c b/src/win/win_sdl.c
index cf5afb809..cd4b26169 100644
--- a/src/win/win_sdl.c
+++ b/src/win/win_sdl.c
@@ -15,10 +15,10 @@
  *
  *
  * Authors:	Fred N. van Kempen, <decwiz@yahoo.com>
- *		Michael Dr�ing, <michael@drueing.de>
+ *		Michael Drüing, <michael@drueing.de>
  *
  *		Copyright 2018-2020 Fred N. van Kempen.
- *		Copyright 2018-2020 Michael Dr�ing.
+ *		Copyright 2018-2020 Michael Drüing.
  *
  *		Redistribution and  use  in source  and binary forms, with
  *		or  without modification, are permitted  provided that the