Updating legal section
diff --git a/README.md b/README.md
index 2e792a3..d73bdd6 100644
--- a/README.md
+++ b/README.md
@@ -39,6 +39,8 @@
FXT1: See the OpenGL extension [GL_3DFX_texture_compression_FXT1](https://www.khronos.org/registry/OpenGL/extensions/3DFX/3DFX_texture_compression_FXT1.txt)
+Also see [Intel® Open Source HD Graphics Programmers' Reference Manual (PRM)](https://01.org/sites/default/files/documentation/intel-gfx-bspec-osrc-chv-bsw-vol05-memory-views.pdf). This reference manual details how to encode FXT1, ETC1, ETC2, EAC, DXT/BC1-3, BC4/5/7, and ASTC.
+
### Release notes
9/26/19 release notes:
