This is a minor nit.  The reference manual does not direct user to do `(use-modules (sxml transform))'

The following patch is wrt guile-2.1.7/doc/ref/sxml.texi

--- sxml.texi.orig 2017-02-25 06:33:38.000000000 -0800
+++ sxml.texi 2017-02-25 06:36:00.000000000 -0800
@@ -457,6 +457,8 @@
 @node Transforming SXML
 @subsection Transforming SXML
 @subsubsection Overview
+@code{(sxml transform)} defines a number of procedures for transforming
+SXML, analogous to using XSL for XML.
 @heading SXML expression tree transformers
 @subheading Pre-Post-order traversal of a tree and creation of a new tree
 @smallexample