add note on sources in readme

README.md

@@ -1,5 +1,8 @@
 
-original source: https://github.com/itfoundry/hind-siliguri
-
-Hind Siliguri contains malformed glyph for Bengali Digit One "১" in its regular, medium, and semi-bold weights.
+The [Hind Siliguri](https://fonts.google.com/specimen/Hind+Siliguri) typeface contains malformed glyphs for Bengali Digit One "১" in its regular, medium, and semi-bold weights.
 I've fixed these for my personal use and decided to share here until original sources and distributions are updated.
+
+#### Note on sources
+
+original source is here: https://github.com/itfoundry/hind-siliguri
+But the build instructions in ITF's repo seems outdated, so I've edited their published TTF files in fontforge, creating the SFD and TTF files available in this repository.