diff --git a/config/checkstyle/checkstyle.xml b/config/checkstyle/checkstyle.xml
index 5bc16ede..a84e41b8 100644
--- a/config/checkstyle/checkstyle.xml
+++ b/config/checkstyle/checkstyle.xml
@@ -1,5 +1,5 @@
 <?xml version="1.0"?>
-<!DOCTYPE module PUBLIC "-//Puppy Crawl//DTD Check Configuration 1.3//EN" "http://www.puppycrawl.com/dtds/configuration_1_3.dtd">
+<!DOCTYPE module PUBLIC "-//Puppy Crawl//DTD Check Configuration 1.3//EN" "https://checkstyle.org/dtds/configuration_1_3.dtd">
 <module name="com.puppycrawl.tools.checkstyle.Checker">
 	<module name="io.spring.javaformat.checkstyle.SpringChecks" />
 </module>