diff --git a/chapters/999-references.md b/chapters/999-references.md
index 626baf5..9cefa37 100644
--- a/chapters/999-references.md
+++ b/chapters/999-references.md
@@ -4,6 +4,13 @@
 - [PyroGuide wiki (hosted at PyroData.com)](https://pyrodata.com/PyroGuide/default.htm)
 - [Alan's lab Pyrotechnics (vk2zay.net)](http://www.vk2zay.net/category/4)
 - [Pyrotechnics FAQ rec.pyrotechnics (stason.org)](https://stason.org/TULARC/entertainment/pyrotechnics/index.html)
+- [Pyrotechnics Guild International](https://www.pgi.org)
+- [Fireworking.com - Hosted by ned gorski](https://fireworking.com/)
+
+## Forums
+
+- [Fireworking.com Forum](https://fireworking.com/forum)
+- [APC Forum](https://www.amateurpyro.com/forums)
 
 ## Databases
 
@@ -14,3 +21,15 @@
 ## Wikipedia
 
 - [Chemical substance](https://en.wikipedia.org/wiki/Chemical_substance)
+- [Gunpower](https://en.wikipedia.org/wiki/Gunpowder)
+- [Pyrotechnic composition](https://en.wikipedia.org/wiki/Pyrotechnic_composition)
+- [Pyrotechnic colorant](https://en.wikipedia.org/wiki/Pyrotechnic_colorant)
+
+## Internet archive (web.archive.org)
+
+- [Practical Pyrotechnics - wfvisser.dds.nl](https://web.archive.org/web/20070205044811/http://www.wfvisser.dds.nl/indexEN.html)
+- [Pyroguide.com](https://web.archive.org/web/20071001110311/http://www.pyroguide.com/index.php?title=Main_Page)
+- [Krimzon Pyro - carpathiahost.net](https://web.archive.org/web/20160307162211/http://krimzonpyro.com.ve.carpathiahost.net/)
+- [Krimzon Pyro - krimzonpyro.com](https://web.archive.org/web/20040729212141/http://krimzonpyro.com/)
+- [Dimock's Pyro Page - pyropage.com](https://web.archive.org/web/20060101062943/http://www.pyropage.com/)
+- [pyrodb.org](https://web.archive.org/web/20170907123333/http://www.pyrodb.org)