diff --git a/to_vp9/README.md b/to_vp9/README.md
index 0a10cee..1de692b 100644
--- a/to_vp9/README.md
+++ b/to_vp9/README.md
@@ -8,10 +8,12 @@ If used on containers with subtitles or audiostreams, this skript will only conv
 
 ### Encoders
 
-Hardware-Encoders like NVENC, VAAPI and QSV depend on your hardware and an enabled [Hardware video acceleration](https://wiki.archlinux.org/title/Hardware_video_acceleration). So not all encoders will be available.
+Hardware-Encoders using NVENC, VAAPI or QSV depend on your hardware and an enabled [Hardware video acceleration](https://wiki.archlinux.org/title/Hardware_video_acceleration). So not all encoders will be available.
 
 #### libvpx-vp9
+Needs a ffmpeg-build with --enable-libvpx
 - https://trac.ffmpeg.org/wiki/Encode/VP9
+- https://ffmpeg.org/ffmpeg-codecs.html#libvpx
 
 #### VP9_vaapi
 
@@ -22,7 +24,7 @@ More Information about this:
 
 #### VP9_qsv
 
-needs intel graphics and ffmpeg with --enable-libmfx or --enable-libvpl.
+needs intel graphics and ffmpeg-build with --enable-libmfx or --enable-libvpl.
 More Information about this:
 - [Differences between libvpl and libmfx](https://www.intel.com/content/www/us/en/developer/articles/technical/onevpl-in-ffmpeg-for-great-streaming-on-intel-gpus.html)
 - https://ffmpeg.org/ffmpeg-all.html#QSV-Encoders