hyperlink at the start of the paragraph confused pdflatex; it saw the
link start while still in vertical mode, which is not allowed. Including
text before the link forces horizontal mode.
\subsection{minidom and the DOM standard \label{minidom-and-dom}}
-\refmodule{xml.dom.minidom} is basically a DOM 1.0-compatible DOM with
-some DOM 2 features (primarily namespace features).
+The \refmodule{xml.dom.minidom} module is essentially a DOM
+1.0-compatible DOM with some DOM 2 features (primarily namespace
+features).
Usage of the DOM interface in Python is straight-forward. The
following mapping rules apply: