diff --git a/shaders/blue-light-filter.glsl.mustache b/shaders/blue-light-filter.glsl.mustache
index 2f4a63d..a5a8c1c 100644
--- a/shaders/blue-light-filter.glsl.mustache
+++ b/shaders/blue-light-filter.glsl.mustache
@@ -12,6 +12,7 @@ uniform sampler2D tex;
 
 /**
  * Color temperature in Kelvin.
+ * https://en.wikipedia.org/wiki/Color_temperature
  *
  * @min 1000.0
  * @max 40000.0