tweak docs

diff --git a/doc/matrices.texi b/doc/matrices.texi
index 3dc19af48ab5a6cc7a34d106a2dc19927a319445..835a7e19ebc863ef95aded353818bf139231992d 100644 (file)
--- a/doc/matrices.texi
+++ b/doc/matrices.texi
@@ -613,6 +613,7 @@ Use @cmd{MATRIX DATA} to convert text input into matrix file format.
 @vindex MATRIX
 @vindex END MATRIX
 
+@node Matrix Overview
 @subsection Overview
 
 @display
@@ -702,6 +703,7 @@ The following matrix commands provide additional support:
 @t{RELEASE} @i{variable}@dots{}.
 @end display
 
+@node Matrix Introduction
 @subsection Introduction
 
 @code{MATRIX} and @code{END MATRIX} enclose a special @pspp{}