Macos: link to formula

diff --git a/installation/macos.md b/installation/macos.md
index 4c738f1f7605406872d35762a962f44d3bfc581e..98a5bbeb7344dac4372554d8ea5688f7406b8935 100644 (file)
--- a/installation/macos.md
+++ b/installation/macos.md
@@ -4,8 +4,8 @@ layout: default
 ---
 
 ## Homebrew (recommended)
-If you use a mac with Homebrew, there already is a formula to install
-dspdfviewer
+If you use a mac with Homebrew, there already is [a formula][formula]
+to install dspdfviewer
 
 {% highlight bash %}
 brew install dspdfviewer
@@ -30,3 +30,5 @@ to pass its installation prefix to `cmake`:
 ```bash
 cmake /path/to/source -DSomeOption=ON -DCMAKE_PREFIX_PATH=$(brew --prefix qt5)
 ```
+
+[formula]: https://github.com/Homebrew/homebrew-core/blob/master/Formula/dspdfviewer.rb