pgsql: Updates to the bibliography.

Log Message:
-----------
Updates to the bibliography. Patch from Michael Fuhr.

Modified Files:
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pgsql/doc/src/sgml:
biblio.sgml (r1.20 -> r1.21)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/biblio.sgml.diff?r1=1.20&r2=1.21)
geqo.sgml (r1.28 -> r1.29)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/geqo.sgml.diff?r1=1.28&r2=1.29)
sql.sgml (r1.34 -> r1.35)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/sql.sgml.diff?r1=1.34&r2=1.35)