src/aubio.h: fix minor typo

diff --git a/src/aubio.h b/src/aubio.h
index 7a27567..b0cceb4 100644 (file)
--- a/src/aubio.h
+++ b/src/aubio.h
@@ -109,7 +109,7 @@
   \endcode
 
   Several examples of C programs are available in the \p examples/ and \p tests/src
-  directory of the source tree.
+  directories of the source tree.
 
   \subsection unstable_api Unstable API