diff --git a/doc/src/sgml/ecpg.sgml b/doc/src/sgml/ecpg.sgml
index 9aa0343eef..9f65b8beb1 100644
--- a/doc/src/sgml/ecpg.sgml
+++ b/doc/src/sgml/ecpg.sgml
@@ -1,6 +1,6 @@
 <!-- doc/src/sgml/ecpg.sgml -->
 
-<chapter id="ecpg">
+<chapter id="ecpg" xreflabel="ecpg">
  <title><application>ECPG</application> - Embedded <acronym>SQL</acronym> in C</title>
 
  <indexterm zone="ecpg"><primary>embedded SQL</primary><secondary>in C</secondary></indexterm>
diff --git a/doc/src/sgml/geqo.sgml b/doc/src/sgml/geqo.sgml
index 5120dfbb42..fb96511846 100644
--- a/doc/src/sgml/geqo.sgml
+++ b/doc/src/sgml/geqo.sgml
@@ -1,6 +1,6 @@
 <!-- doc/src/sgml/geqo.sgml -->
 
- <chapter id="geqo">
+ <chapter id="geqo" xreflabel="geqo">
   <title>Genetic Query Optimizer</title>
 
   <para>
diff --git a/doc/src/sgml/gin.sgml b/doc/src/sgml/gin.sgml
index cc7cd1ed2c..8a4e7bb041 100644
--- a/doc/src/sgml/gin.sgml
+++ b/doc/src/sgml/gin.sgml
@@ -1,6 +1,6 @@
 <!-- doc/src/sgml/gin.sgml -->
 
-<chapter id="gin">
+<chapter id="gin" xreflabel="gin">
 <title>GIN Indexes</title>
 
    <indexterm>
diff --git a/doc/src/sgml/gist.sgml b/doc/src/sgml/gist.sgml
index beed6521eb..858101eeef 100644
--- a/doc/src/sgml/gist.sgml
+++ b/doc/src/sgml/gist.sgml
@@ -1,6 +1,6 @@
 <!-- doc/src/sgml/gist.sgml -->
 
-<chapter id="gist">
+<chapter id="gist" xreflabel="gist">
 <title>GiST Indexes</title>
 
    <indexterm>
diff --git a/doc/src/sgml/libpq.sgml b/doc/src/sgml/libpq.sgml
index ee3b4e7435..6675440922 100644
--- a/doc/src/sgml/libpq.sgml
+++ b/doc/src/sgml/libpq.sgml
@@ -1,6 +1,6 @@
 <!-- doc/src/sgml/libpq.sgml -->
 
-<chapter id="libpq">
+<chapter id="libpq" xreflabel="libpq">
  <title><application>libpq</application> - C Library</title>
 
  <indexterm zone="libpq">
diff --git a/doc/src/sgml/plperl.sgml b/doc/src/sgml/plperl.sgml
index 967efba3b5..cf424f8d02 100644
--- a/doc/src/sgml/plperl.sgml
+++ b/doc/src/sgml/plperl.sgml
@@ -1,6 +1,6 @@
 <!-- doc/src/sgml/plperl.sgml -->
 
- <chapter id="plperl">
+ <chapter id="plperl" xreflabel="PL/Perl">
   <title>PL/Perl - Perl Procedural Language</title>
 
   <indexterm zone="plperl">
diff --git a/doc/src/sgml/plpgsql.sgml b/doc/src/sgml/plpgsql.sgml
index 95206ebfc1..87aab8730a 100644
--- a/doc/src/sgml/plpgsql.sgml
+++ b/doc/src/sgml/plpgsql.sgml
@@ -1,6 +1,6 @@
 <!-- doc/src/sgml/plpgsql.sgml -->
 
-<chapter id="plpgsql">
+<chapter id="plpgsql" xreflabel="PL/pgSQL">
   <title><application>PL/pgSQL</application> - <acronym>SQL</acronym> Procedural Language</title>
 
  <indexterm zone="plpgsql">
diff --git a/doc/src/sgml/plpython.sgml b/doc/src/sgml/plpython.sgml
index 60a5907464..8dfa45c734 100644
--- a/doc/src/sgml/plpython.sgml
+++ b/doc/src/sgml/plpython.sgml
@@ -1,6 +1,6 @@
 <!-- doc/src/sgml/plpython.sgml -->
 
-<chapter id="plpython">
+<chapter id="plpython" xreflabel="PL/Python">
  <title>PL/Python - Python Procedural Language</title>
 
  <indexterm zone="plpython"><primary>PL/Python</primary></indexterm>
diff --git a/doc/src/sgml/spi.sgml b/doc/src/sgml/spi.sgml
index 6f4f3bae6f..c1185dc4f9 100644
--- a/doc/src/sgml/spi.sgml
+++ b/doc/src/sgml/spi.sgml
@@ -1,6 +1,6 @@
 <!-- doc/src/sgml/spi.sgml -->
 
-<chapter id="spi">
+<chapter id="spi" xreflabel="spi">
  <title>Server Programming Interface</title>
 
  <indexterm zone="spi">
diff --git a/doc/src/sgml/vacuumlo.sgml b/doc/src/sgml/vacuumlo.sgml
index 0b4dfc2b17..93aad00115 100644
--- a/doc/src/sgml/vacuumlo.sgml
+++ b/doc/src/sgml/vacuumlo.sgml
@@ -1,6 +1,6 @@
 <!-- doc/src/sgml/vacuumlo.sgml -->
 
-<refentry id="vacuumlo">
+<refentry id="vacuumlo" xreflabel="vacuumlo">
  <indexterm zone="vacuumlo">
   <primary>vacuumlo</primary>
  </indexterm>