adds check for files in make script

make.sh

@@ -4,6 +4,7 @@ FILENAME="ResearchProposal"
 
 IN="${FILENAME}.md"
 OUT="${FILENAME}.pdf"
+OUT_MOD="${FILENAME}-Erkl.pdf"
 
 # Generate the PDF from Markdown
 echo "Generating PDF..."
@@ -22,7 +23,7 @@ fi
 
 # Insert Erklärung.pdf at the end of the PDF
 echo "Modifying the PDF..."
-./modify-pdf.sh "$OUT" "resources/Erklärung.pdf" "$OUT"
+./modify-pdf.sh "$OUT" "resources/Erklärung.pdf" "$OUT_MOD"
 
 # remove last page for osf.io
 echo "Removing last page for OSF.io output and saving to OSF-$OUT"