Update book links in latest.rst

Author: drbruced12

latest.rst

@@ -13,10 +13,12 @@ the Internet today.
 `Book Series: <https://systemsapproach.org/books/>`__ Also check out
 our companion books that cover emerging topics in more depth.
 
-* `Private 5G: A Systems Approach <https://5G.systemsapproach.org>`__
+* `What We Talk About When We Talk About Systems <https://systemsapproach.org/books/#essaybook>`__
 
-* `Software-Defined Networks: A Systems Approach <https://sdn.systemsapproach.org>`__
+* `Private 5G: A Systems Approach <https://systemsapproach.org/books/#5gbook>`__
 
-* `TCP Congestion Control: A Systems Approach <https://tcpcc.systemsapproach.org>`__
+* `Software-Defined Networks: A Systems Approach <https://systemsapproach.org/books/#sdnbook>`__
+
+* `TCP Congestion Control: A Systems Approach <https://systemsapproach.org/books/#tcpbook>`__
 
 .. * `Edge Cloud Operations: A Systems Approach <https://ops.systemsapproach.org>`__