diff --git a/README.md b/README.md
index 0465879..72ab4b8 100644
--- a/README.md
+++ b/README.md
@@ -39,6 +39,8 @@ For generating the images from PlantUML sources (`*.plantuml`), [PlantUML](https
 
 For pdf output the LaTeX builder is used, so `latex` and `pdflatex` need to be installed.
 
+For document generation `make` and latexmk` is required.
+
 ### Running the document generation via make
 
 The top level directory contains a Makefile, for generation with all output formats use