README.md in usps_flags-0.3.7 vs README.md in usps_flags-0.3.8

@@ -126,9 +126,14 @@
 
 - You can explicitly set `svg_file` to `""` to suppress printing the SVG content
   to console/log.
 - Calling `.png` requires `png_file` to be set.
 
+## Burgees Extension
+
+There is an extension to this gem for handling squadron burgees:
+[USPSFlags::Burgees](https://github.com/jfiander/usps-flags_burgees)
+
 ## Security
 
 This gem is cryptographically signed. To be sure the gem code hasn’t been
 tampered with: