d = Doctype(name = "section",
public = c("-//OASIS//DTD DocBook XML V4.2//EN",
"http://oasis-open.org/docbook/xml/4.2/docbookx.dtd"))
as(d, "character")
# this call switches the system to the URI associated with the PUBLIC element.
d = Doctype(name = "section",
public = c("-//OASIS//DTD DocBook XML V4.2//EN"),
system = "http://oasis-open.org/docbook/xml/4.2/docbookx.dtd")
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