List<String> refs = poData.getReferences();
refs.add("ref1.xml:7");
refs.add("ref1.xml:21");
Resource doc = newDoc(id, textflow);
PoHeader poHeader = new PoHeader();
poHeader.setComment("poheader comment");
List<HeaderEntry> poEntries = poHeader.getEntries();
poEntries.add(new HeaderEntry("Project-Id-Version", "en"));
poEntries.add(new HeaderEntry("Content-Type",
"application/x-publican; charset=UTF-8\n"));
doc.getExtensions(true).add(poHeader);