diff --git a/README.md b/README.md
index 67a9ae7278cc494e01bbe8841fc8533b4e6961a5..2780c03159622cef88059725d3923aa970729258 100644
--- a/README.md
+++ b/README.md
@@ -238,6 +238,7 @@ Alternatively, if you want to build everything, manually install the following p
 - `texlive-latex-recommended` (or `latex-beamer` on older systems)
 - `texlive-science` (or `texlive-math-extra` on older systems) (for amstex)
 - `texinfo`
+- `lmodern` (for macroprocessor PDF)
 - `latex2html`
 - `doxygen`