diff --git a/config/checkstyle/checkstyle.xml b/config/checkstyle/checkstyle.xml
index 23c7eb6..f077801 100644
--- a/config/checkstyle/checkstyle.xml
+++ b/config/checkstyle/checkstyle.xml
@@ -1,6 +1,6 @@
 <?xml version="1.0"?>
 <!DOCTYPE module PUBLIC "-//Puppy Crawl//DTD Check Configuration 1.3//EN"
-		"http://www.puppycrawl.com/dtds/configuration_1_3.dtd">
+		"https://www.puppycrawl.com/dtds/configuration_1_3.dtd">
 <module name="Checker">
 	<!-- Suppressions -->
 	<module name="SuppressionFilter">
diff --git a/config/checkstyle/suppressions.xml b/config/checkstyle/suppressions.xml
index 915c20f..cf19e97 100644
--- a/config/checkstyle/suppressions.xml
+++ b/config/checkstyle/suppressions.xml
@@ -1,6 +1,6 @@
 <?xml version="1.0"?>
 <!DOCTYPE suppressions PUBLIC "-//Puppy Crawl//DTD Suppressions 1.1//EN"
-		"http://www.puppycrawl.com/dtds/suppressions_1_1.dtd">
+		"https://www.puppycrawl.com/dtds/suppressions_1_1.dtd">
 <suppressions>
 	<suppress files=".+Application\.java" checks="HideUtilityClassConstructor"/>
 	<suppress files=".+Configuration\.java" checks="HideUtilityClassConstructor"/>
diff --git a/settings.xml b/settings.xml
index cf86357..829f33c 100644
--- a/settings.xml
+++ b/settings.xml
@@ -1,7 +1,7 @@
 <settings xmlns="http://maven.apache.org/SETTINGS/1.0.0"
 		  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 		  xsi:schemaLocation="http://maven.apache.org/SETTINGS/1.0.0
-                      http://maven.apache.org/xsd/settings-1.0.0.xsd">
+                      https://maven.apache.org/xsd/settings-1.0.0.xsd">
 
 	<servers>
 		<server>