diff --git a/docs/ray_intersect.tex b/docs/ray_intersect.tex
index b822c1ceca..bf506dd022 100644
--- a/docs/ray_intersect.tex
+++ b/docs/ray_intersect.tex
@@ -1,4 +1,4 @@
-% build me with xelatex + pdflatex
+% build me with xelatex + bibtex
 \documentclass[a4paper,10pt]{article}
 
 \usepackage{hyperref}