diff --git a/Doc/copyright.tex b/Doc/copyright.tex
index 465ca28..4669ff46 100644
--- a/Doc/copyright.tex
+++ b/Doc/copyright.tex
@@ -1,4 +1,4 @@
-Copyright \copyright\ 1991-1995 by Stichting Mathematisch Centrum,
+Copyright \copyright{} 1991-1995 by Stichting Mathematisch Centrum,
 Amsterdam, The Netherlands.
 
 \begin{center}
diff --git a/Doc/texinputs/copyright.tex b/Doc/texinputs/copyright.tex
index 465ca28..4669ff46 100644
--- a/Doc/texinputs/copyright.tex
+++ b/Doc/texinputs/copyright.tex
@@ -1,4 +1,4 @@
-Copyright \copyright\ 1991-1995 by Stichting Mathematisch Centrum,
+Copyright \copyright{} 1991-1995 by Stichting Mathematisch Centrum,
 Amsterdam, The Netherlands.
 
 \begin{center}