diff --git a/src/duck-extract.scm b/src/duck-extract.scm
index 6953a5c..30c83fd 100644
--- a/src/duck-extract.scm
+++ b/src/duck-extract.scm
@@ -43,6 +43,9 @@
 	  dt)
      " ")))
 
+ (define (print-duck-signature sig)
+   (print "    " sig))
+
  (define (print-duck-module sec)
    (print "## " (cadr sec) " [module]")
    (newline)
@@ -72,7 +75,7 @@
    (newline)
    (print "### " (cadr sec) " [procedure]")
    (newline)
-   (print "    " (cons (cadr sec) (cadddr sec)))
+   (print-duck-signature (cons (cadr sec) (cadddr sec)))
    (newline)
    (print-duck-text (caddr sec)))