Update index.html

index.html

@@ -121,7 +121,7 @@ <h2>Computer Systems Principles and Concurrent Programming</h2>
   <ul>
     <li><b><a style="text-decoration:none" href="https://linuxcommand.org/tlcl.php" target="_blank">The Linux Command Line</a></b></li>
     <li><b><a style="text-decoration:none" href="https://linuxcommand.org/tlcl.php#AWTLCL" target="_blank">Adventures with the Linux Command Line</a></b></li>
-    <li><b><a style="text-decoration:none" href="https://pragprog.com/titles/bhcldev/small-sharp-software-tools/" target="_blank">Small, Sharp Software Tools</a></b></li>
+    <li><b><a style="text-decoration:none" href="https://smallsharpsoftwaretools.com/" target="_blank">Small, Sharp Software Tools</a></b></li>
     <li><b><a style="text-decoration:none" href="https://greenteapress.com/wp/semaphores/" target="_blank">The Little Book of Semaphores</a></b></li>
     <li><a style="text-decoration:none" href="https://man7.org/tlpi/" target="_blank">The Linux Programming Interface</a></li>
     <li><a style="text-decoration:none" href="http://www.apuebook.com/" target="_blank">Advanced Programming in the UNIX Environment</a></li>