diff --git a/doc/src/sgml/acronyms.sgml b/doc/src/sgml/acronyms.sgml
index ecec020dffa..58d0d90fece 100644
--- a/doc/src/sgml/acronyms.sgml
+++ b/doc/src/sgml/acronyms.sgml
@@ -50,7 +50,7 @@
     <term><acronym>ASCII</acronym></term>
     <listitem>
      <para>
-      <ulink url="https://en.wikipedia.org/wiki/Ascii">American Standard
+      <ulink url="https://en.wikipedia.org/wiki/ASCII">American Standard
       Code for Information Interchange</ulink>
      </para>
     </listitem>
@@ -158,7 +158,7 @@
     <term><acronym>DBMS</acronym></term>
     <listitem>
      <para>
-      <ulink url="https://en.wikipedia.org/wiki/Dbms">Database Management
+      <ulink url="https://en.wikipedia.org/wiki/Database#Database_management_system">Database Management
       System</ulink>
      </para>
     </listitem>
@@ -169,7 +169,7 @@
     <listitem>
      <para>
       <ulink
-      url="https://en.wikipedia.org/wiki/Data_Definition_Language">Data
+      url="https://en.wikipedia.org/wiki/Data_definition_language">Data
       Definition Language</ulink>, SQL commands such as <command>CREATE
       TABLE</command>, <command>ALTER USER</command>
      </para>
@@ -181,7 +181,7 @@
     <listitem>
      <para>
       <ulink
-      url="https://en.wikipedia.org/wiki/Data_Manipulation_Language">Data
+      url="https://en.wikipedia.org/wiki/Data_manipulation_language">Data
       Manipulation Language</ulink>, SQL commands such as <command>INSERT</command>,
       <command>UPDATE</command>, <command>DELETE</command>
      </para>
@@ -269,7 +269,7 @@
     <listitem>
      <para>
       <ulink
-      url="https://en.wikipedia.org/wiki/Git_(software)">Git</ulink>
+      url="https://en.wikipedia.org/wiki/Git">Git</ulink>
      </para>
     </listitem>
    </varlistentry>
@@ -278,7 +278,7 @@
     <term><acronym>GMT</acronym></term>
     <listitem>
      <para>
-      <ulink url="https://en.wikipedia.org/wiki/GMT">Greenwich Mean Time</ulink>
+      <ulink url="https://en.wikipedia.org/wiki/Greenwich_Mean_Time">Greenwich Mean Time</ulink>
      </para>
     </listitem>
    </varlistentry>
@@ -368,7 +368,7 @@
     <term><acronym>ISSN</acronym></term>
     <listitem>
      <para>
-      <ulink url="https://en.wikipedia.org/wiki/Issn">International Standard
+      <ulink url="https://en.wikipedia.org/wiki/ISSN">International Standard
       Serial Number</ulink>
      </para>
     </listitem>
@@ -461,7 +461,7 @@
     <listitem>
      <para>
       <ulink
-      url="https://en.wikipedia.org/wiki/Visual_C++"><productname>Microsoft
+      url="https://en.wikipedia.org/wiki/Microsoft_Visual_C%2B%2B"><productname>Microsoft
       Visual C</productname></ulink>
      </para>
     </listitem>
@@ -511,7 +511,7 @@
     <term><acronym>OLAP</acronym></term>
     <listitem>
      <para>
-      <ulink url="https://en.wikipedia.org/wiki/Olap">Online Analytical
+      <ulink url="https://en.wikipedia.org/wiki/Online_analytical_processing">Online Analytical
       Processing</ulink>
      </para>
     </listitem>
@@ -521,7 +521,7 @@
     <term><acronym>OLTP</acronym></term>
     <listitem>
      <para>
-      <ulink url="https://en.wikipedia.org/wiki/OLTP">Online Transaction
+      <ulink url="https://en.wikipedia.org/wiki/Online_transaction_processing">Online Transaction
       Processing</ulink>
      </para>
     </listitem>
@@ -531,7 +531,7 @@
     <term><acronym>ORDBMS</acronym></term>
     <listitem>
      <para>
-      <ulink url="https://en.wikipedia.org/wiki/ORDBMS">Object-Relational
+      <ulink url="https://en.wikipedia.org/wiki/Object%E2%80%93relational_database">Object-Relational
       Database Management System</ulink>
      </para>
     </listitem>
@@ -542,7 +542,7 @@
     <listitem>
      <para>
       <ulink
-      url="https://en.wikipedia.org/wiki/Pluggable_Authentication_Modules">Pluggable
+      url="https://en.wikipedia.org/wiki/Pluggable_authentication_module">Pluggable
       Authentication Modules</ulink>
      </para>
     </listitem>
@@ -609,7 +609,7 @@
     <listitem>
      <para>
       <ulink
-      url="https://en.wikipedia.org/wiki/Relational_database_management_system">Relational
+      url="https://en.wikipedia.org/wiki/Relational_database#RDBMS">Relational
       Database Management System</ulink>
      </para>
     </listitem>
@@ -630,7 +630,7 @@
     <term><acronym>SGML</acronym></term>
     <listitem>
      <para>
-      <ulink url="https://en.wikipedia.org/wiki/SGML">Standard Generalized
+      <ulink url="https://en.wikipedia.org/wiki/Standard_Generalized_Markup_Language">Standard Generalized
       Markup Language</ulink>
      </para>
     </listitem>
@@ -698,7 +698,7 @@
     <term><acronym>SSL</acronym></term>
     <listitem>
      <para>
-      <ulink url="https://en.wikipedia.org/wiki/Secure_Sockets_Layer">Secure Sockets Layer</ulink>
+      <ulink url="https://en.wikipedia.org/wiki/Transport_Layer_Security#SSL_1.0,_2.0,_and_3.0">Secure Sockets Layer</ulink>
      </para>
     </listitem>
    </varlistentry>
@@ -717,7 +717,7 @@
     <term><acronym>SYSV</acronym></term>
     <listitem>
      <para>
-      <ulink url="https://en.wikipedia.org/wiki/System_V">Unix System V</ulink>
+      <ulink url="https://en.wikipedia.org/wiki/UNIX_System_V">Unix System V</ulink>
      </para>
     </listitem>
    </varlistentry>
@@ -806,7 +806,7 @@
     <term><acronym>UTF8</acronym></term>
     <listitem>
      <para>
-      <ulink url="https://en.wikipedia.org/wiki/Utf8">Eight-Bit Unicode
+      <ulink url="https://en.wikipedia.org/wiki/UTF-8">Eight-Bit Unicode
       Transformation Format</ulink>
      </para>
     </listitem>
diff --git a/doc/src/sgml/isn.sgml b/doc/src/sgml/isn.sgml
index ea2aabc87d7..bd7a221f731 100644
--- a/doc/src/sgml/isn.sgml
+++ b/doc/src/sgml/isn.sgml
@@ -397,7 +397,7 @@ SELECT isbn13(id) FROM test;
    The prefixes used for hyphenation were also compiled from:
    <itemizedlist>
     <listitem><para><ulink url="https://www.gs1.org/standards/id-keys"></ulink></para></listitem>
-    <listitem><para><ulink url="https://en.wikipedia.org/wiki/List_of_ISBN_identifier_groups"></ulink></para></listitem>
+    <listitem><para><ulink url="https://en.wikipedia.org/wiki/List_of_ISBN_registration_groups"></ulink></para></listitem>
     <listitem><para><ulink url="https://www.isbn-international.org/content/isbn-users-manual"></ulink></para></listitem>
     <listitem><para><ulink url="https://en.wikipedia.org/wiki/International_Standard_Music_Number"></ulink></para></listitem>
     <listitem><para><ulink url="https://www.ismn-international.org/ranges.html"></ulink></para></listitem>
diff --git a/doc/src/sgml/sepgsql.sgml b/doc/src/sgml/sepgsql.sgml
index 1b848f1977c..bc308e3142d 100644
--- a/doc/src/sgml/sepgsql.sgml
+++ b/doc/src/sgml/sepgsql.sgml
@@ -794,7 +794,7 @@ ERROR:  SELinux: security policy violation
   <title>External Resources</title>
   <variablelist>
    <varlistentry>
-    <term><ulink url="https://wiki.postgresql.org/wiki/SEPostgreSQL">SE-PostgreSQL Introduction</ulink></term>
+    <term><ulink url="https://wiki.postgresql.org/wiki/SEPostgreSQL_Introduction">SE-PostgreSQL Introduction</ulink></term>
     <listitem>
      <para>
       This wiki page provides a brief overview, security design, architecture,