diff --git a/slides/build.sh b/slides/build.sh
index f93d6af421750b225f6e0a32358d5c2b802ef469..f54e3b6497b4fca2ade085934f0402163d4d73cc 100644
--- a/slides/build.sh
+++ b/slides/build.sh
@@ -1,3 +1,18 @@
-FILENAME=$1
-knit $FILENAME.Rnw
-pdflatex $FILENAME.tex
+if [ "$1" = "-h" ]; then
+    echo 'Usage:'
+    echo '  $1: filename without extension, e.g. `slides`.'
+    echo '  $2: {0, 1}, remove LaTeX auxiliary files (.log, .aux, ...).'
+else
+    FILENAME=$1
+    echo "\nConverting Rnw to tex.\n"
+    knit $FILENAME.Rnw
+    echo "\nConverting tex to PDF.\n"
+    pdflatex $FILENAME.tex
+fi
+
+if [ "$#" -eq 2 ]; then
+    if [ "$2" -eq 1 ]; then
+        echo "\nDeleting LaTeX auxiliary files.\n"
+        rubber --clean $FILENAME
+    fi
+fi