Use a uniform chapter title for all of the procedural languages.

doc/src/sgml/plperl.sgml

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-$Header: /cvsroot/pgsql/doc/src/sgml/plperl.sgml,v 2.2 2000/03/31 03:27:41 thomas Exp $
+$Header: /cvsroot/pgsql/doc/src/sgml/plperl.sgml,v 2.3 2000/03/31 06:17:21 thomas Exp $
 -->
 
  <chapter id="pl-perl">
-  <title>Perl Procedural Language</title>
+  <title>PL/perl - Perl Procedural Language</title>
 
   <para>
    This chapter describes how to compile, install and

doc/src/sgml/plsql.sgml

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-$Header: /cvsroot/pgsql/doc/src/sgml/Attic/plsql.sgml,v 2.2 2000/03/31 03:27:41 thomas Exp $
+$Header: /cvsroot/pgsql/doc/src/sgml/Attic/plsql.sgml,v 2.3 2000/03/31 06:17:21 thomas Exp $
 -->
 
  <chapter>
-  <title>PL/pgSQL</title>
+  <title>PL/pgSQL - SQL Procedural Language</title>
 
   <para>
    PL/pgSQL is a loadable procedural language for the

doc/src/sgml/pltcl.sgml

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-$Header: /cvsroot/pgsql/doc/src/sgml/pltcl.sgml,v 2.2 2000/03/31 03:27:41 thomas Exp $
+$Header: /cvsroot/pgsql/doc/src/sgml/pltcl.sgml,v 2.3 2000/03/31 06:17:21 thomas Exp $
 -->
 
  <chapter>
-  <title>PL/Tcl</title>
+  <title>PL/Tcl - TCL Procedural Language</title>
 
   <para>
    PL/Tcl is a loadable procedural language for the