diff --git a/README.md b/README.md
index b1263f1..82f201b 100644
--- a/README.md
+++ b/README.md
@@ -17,16 +17,24 @@ WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION,
 ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
 SOFTWARE.
 
-## License of media (textures and sounds)
+## License and attribution of media (textures and sounds)
 
-Attribution-ShareAlike 3.0 Unported (CC BY-SA 3.0)
-http://creativecommons.org/licenses/by-sa/3.0/
+### [Public Domain Dedication (CC0 1.0)](https://creativecommons.org/publicdomain/zero/1.0/)
 
-## Authors of media files
+ * `nether_portal_teleport.ogg` is a timing adjusted version of "teleport" by outroelison (https://freesound.org/people/outroelison), used under CC0 1.0
 
-Everything not listed in here:
-Copyright (C) 2013 PilzAdam
+### [Attribution 3.0 Unported (CC BY 3.0)](https://creativecommons.org/licenses/by/3.0/)
+ 
+ * `nether_portal_ambient.ogg` & `nether_portal_ambient.0.ogg` are extractions from "Deep Cinematic Rumble Stereo" by [Patrick Lieberkind](http://www.lieberkindvisuals.dk)
+ * `nether_portal_extinguish.ogg` is an extraction from "Tight Laser Weapon Hit Scifi" by damjancd (https://freesound.org/people/damjancd), used under CC BY 3.0
+ * `nether_portal_ignite.ogg` is a derivative of "Flame Ignition" by hykenfreak (https://freesound.org/people/hykenfreak), used under CC BY 3.0. "Nether Portal ignite" is licensed under CC BY 3.0 by Treer.
 
- - nether_rack.png: Zeg9
- - nether_glowstone.png: BlockMen
- - nether_book_*: Treer
+### [Attribution-ShareAlike 4.0 International (CC BY-SA 4.0)](https://creativecommons.org/licenses/by-sa/4.0/)
+ * `nether_book_`* (files starting with "nether_book"): Treer, 2019
+ * `nether_portal_ignition_failure.ogg`: Treer, 2019
+
+### [Attribution-ShareAlike 3.0 Unported (CC BY-SA 3.0)](http://creativecommons.org/licenses/by-sa/3.0/)
+ * `nether_rack.png`: Zeg9
+ * `nether_glowstone.png`: BlockMen
+
+All other media: Copyright © 2013 PilzAdam, licensed under CC BY-SA 3.0 by PilzAdam.
\ No newline at end of file
diff --git a/sounds/nether_book_open.ogg b/sounds/nether_book_open.ogg
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diff --git a/sounds/nether_portal_ambient.0.ogg b/sounds/nether_portal_ambient.0.ogg
new file mode 100644
index 0000000..e6d339f
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diff --git a/sounds/nether_portal_ambient.ogg b/sounds/nether_portal_ambient.ogg
new file mode 100644
index 0000000..ea08651
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diff --git a/sounds/nether_portal_extinguish.ogg b/sounds/nether_portal_extinguish.ogg
new file mode 100644
index 0000000..60efef2
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diff --git a/sounds/nether_portal_ignite.ogg b/sounds/nether_portal_ignite.ogg
new file mode 100644
index 0000000..40f7094
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diff --git a/sounds/nether_portal_ignition_failure.ogg b/sounds/nether_portal_ignition_failure.ogg
new file mode 100644
index 0000000..e1fd0e5
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diff --git a/sounds/nether_portal_teleport.ogg b/sounds/nether_portal_teleport.ogg
new file mode 100644
index 0000000..9b62b62
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