diff --git a/README.md b/README.md
index 15a2b17..e8e873d 100644
--- a/README.md
+++ b/README.md
@@ -8,6 +8,16 @@ I created a `\Scans` directory in my `\Home` directory<sup>1</sup> and use this
 
     $ pdftk *.pdf cat output newfile.pdf
 
+If you have to scan the front sides and back sides separately, use
+
+    $ pdftk A=001a.pdf B=001b.pdf shuffle A B output 001.pdf
+
+where we assume that 001a.pdf contains the right-hand (i.e., odd-numbered) pages and 001b.pdf contains the left-hand (i.e., even-numbered) pages.
+
+Chances are your document feeder will scan the left-hand pages in reverse order. In that case, use this command:
+
+    pdftk A=001a.pdf B=001b.pdf shuffle A Bend-1 output 001.pdf
+
 If I have to break into a project, I will just create a subdirectory for the current project and dump all those scans in there temporarily.