diff --git a/app/Config/Constants.php b/app/Config/Constants.php
index 0c1b534..197bfce 100644
--- a/app/Config/Constants.php
+++ b/app/Config/Constants.php
@@ -59,12 +59,12 @@
  | are as follows:
  |
  |    Standard C/C++ Library (stdlibc):
- |       http://www.gnu.org/software/libc/manual/html_node/Exit-Status.html
+ |       https://www.gnu.org/software/libc/manual/html_node/Exit-Status.html
  |       (This link also contains other GNU-specific conventions)
  |    BSD sysexits.h:
- |       http://www.gsp.com/cgi-bin/man.cgi?section=3&topic=sysexits
+ |       https://www.gsp.com/cgi-bin/man.cgi?section=3&topic=sysexits
  |    Bash scripting:
- |       http://tldp.org/LDP/abs/html/exitcodes.html
+ |       https://tldp.org/LDP/abs/html/exitcodes.html
  |
  */
 defined('EXIT_SUCCESS')        || define('EXIT_SUCCESS', 0); // no errors