diff --git a/doc/org/index.org b/doc/org/index.org
index 0a1a69a9f..6ee957a47 100644
--- a/doc/org/index.org
+++ b/doc/org/index.org
@@ -1,3 +1,4 @@
+# -*- coding: utf-8 -*-
 #+TITLE: Spot
 #+SETUPFILE: setup.org
 
diff --git a/doc/org/ltl2tgta.org b/doc/org/ltl2tgta.org
index 30385484f..563aa6627 100644
--- a/doc/org/ltl2tgta.org
+++ b/doc/org/ltl2tgta.org
@@ -1,3 +1,4 @@
+# -*- coding: utf-8 -*-
 #+TITLE: =ltl2tgta=
 #+SETUPFILE: setup.org
 #+HTML_LINK_UP: tools.html
diff --git a/doc/org/randltl.org b/doc/org/randltl.org
index 11554315b..839dc066b 100644
--- a/doc/org/randltl.org
+++ b/doc/org/randltl.org
@@ -1,3 +1,4 @@
+# -*- coding: utf-8 -*-
 #+TITLE: =randltl=
 #+SETUPFILE: setup.org
 #+HTML_LINK_UP: tools.html
diff --git a/doc/org/satmin.org b/doc/org/satmin.org
index 2bb7a792c..edc239fb2 100644
--- a/doc/org/satmin.org
+++ b/doc/org/satmin.org
@@ -1,3 +1,4 @@
+# -*- coding: utf-8 -*-
 #+TITLE: SAT-based Minimization of Deterministic ω-Automata
 #+SETUPFILE: setup.org
 #+HTML_LINK_UP: tools.html
diff --git a/doc/org/tut.org b/doc/org/tut.org
index 64cbee878..d90530bb7 100644
--- a/doc/org/tut.org
+++ b/doc/org/tut.org
@@ -1,3 +1,4 @@
+# -*- coding: utf-8 -*-
 #+TITLE: Code Examples
 #+SETUPFILE: setup.org
 #+HTML_LINK_UP: index.html
diff --git a/doc/org/tut01.org b/doc/org/tut01.org
index 53687e6f6..e84efacd5 100644
--- a/doc/org/tut01.org
+++ b/doc/org/tut01.org
@@ -1,3 +1,4 @@
+# -*- coding: utf-8 -*-
 #+TITLE: Parsing and Printing LTL Formulas
 #+SETUPFILE: setup.org
 #+HTML_LINK_UP: tut.html
diff --git a/doc/org/tut02.org b/doc/org/tut02.org
index 06584971d..b983d08a8 100644
--- a/doc/org/tut02.org
+++ b/doc/org/tut02.org
@@ -1,3 +1,4 @@
+# -*- coding: utf-8 -*-
 #+TITLE: Relabeling Formulas
 #+SETUPFILE: setup.org
 #+HTML_LINK_UP: tut.html
@@ -20,7 +21,7 @@ ltlfilt -ps --relabel=pnn --define -f '"Proc@Here" U ("var > 10" | "var < 4")'
 : (p0) U ((p1) || (p2))
 
 When is this output interesting, you may ask?  It is useful for
-instance if you want to call =ltl2ba= (or any other LTL-to-Büchi
+instance if you want to call =ltl2ba= (or any other LTL-to-Büchi
 translator) using a formula with complex atomic propositions it cannot
 parse.  Then you can pass the rewritten formula to =ltl2ba=, and
 prepend all those =#define= to its output.  For instance:
diff --git a/doc/org/tut10.org b/doc/org/tut10.org
index b3d8ccd48..4f7c8c4ab 100644
--- a/doc/org/tut10.org
+++ b/doc/org/tut10.org
@@ -1,3 +1,4 @@
+# -*- coding: utf-8 -*-
 #+TITLE: Translating an LTL formula into a never claim
 #+SETUPFILE: setup.org
 #+HTML_LINK_UP: tut.html
diff --git a/doc/org/tut20.org b/doc/org/tut20.org
index 5623dd87c..097aaa718 100644
--- a/doc/org/tut20.org
+++ b/doc/org/tut20.org
@@ -1,3 +1,4 @@
+# -*- coding: utf-8 -*-
 #+TITLE: Converting a never claim into HOA
 #+SETUPFILE: setup.org
 #+HTML_LINK_UP: tut.html
diff --git a/doc/org/tut21.org b/doc/org/tut21.org
index 7cc5f85fa..e98ecbbaa 100644
--- a/doc/org/tut21.org
+++ b/doc/org/tut21.org
@@ -1,3 +1,4 @@
+# -*- coding: utf-8 -*-
 #+TITLE: Custom print of an automaton
 #+SETUPFILE: setup.org
 #+HTML_LINK_UP: tut.html
diff --git a/doc/org/tut22.org b/doc/org/tut22.org
index 573df4222..b8b499993 100644
--- a/doc/org/tut22.org
+++ b/doc/org/tut22.org
@@ -1,3 +1,4 @@
+# -*- coding: utf-8 -*-
 #+TITLE: Creating an automaton in C++
 #+SETUPFILE: setup.org
 #+HTML_LINK_UP: tut.html