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\begin{document}

\section*{Draft bibliography for Cornish}

\tableofcontents

\printbibliography[heading=bibintoc,title={Introductions and general histories},keyword=corn:gen]

\printbibliography[heading=bibintoc,title={Old Cornish writing and commentary},keyword=corn:oc]

\printbibliography[heading=bibintoc,title={Middle Cornish writing and commentary},keyword=corn:mc]

\printbibliography[heading=bibintoc,title={Late Cornish writing and commentary},keyword=corn:lc]

\printbibliography[heading=bibintoc,title={Revived Cornish writing and commentary},keyword=corn:revc]

\printbibliography[heading=bibintoc,title={Linguistic works on traditional
  Cornish},keyword=corn:tradling]

\printbibliography[heading=bibintoc,title={Linguistic works on revived Cornish},keyword=corn:revling]

\printbibliography[heading=bibintoc,title={The decline of Cornish},keyword=corn:decl]

\printbibliography[heading=bibintoc,title={Textbooks, dictionaries, grammars: Unified Cornish/Unified Cornish Revised/Kernowek Standard},keyword=corn:ucmat]

\printbibliography[heading=bibintoc,title={Textbooks, dictionaries, grammars: Kernewek Kemmyn},keyword=corn:kkmat]

\printbibliography[heading=bibintoc,title={Textbooks, dictionaries, grammars: Modern Cornish},keyword=corn:rlcmat]

\printbibliography[heading=bibintoc,title={Textbooks, dictionaries, grammars: SWF},keyword=corn:swfmat]

\printbibliography[heading=bibintoc,title={Textbooks, dictionaries, grammars: Early and other varieties},keyword=corn:altmat]

\printbibliography[heading=bibintoc,title={Spelling/varieties debate 1: Pre-Kernewek Kemmyn},keyword=corn:orth1]

\printbibliography[heading=bibintoc,title={Spelling/varieties debate 2: Post-Kernewek Kemmyn},keyword=corn:orth2]

\printbibliography[heading=bibintoc,title={Spelling/varieties debate 3: The SWF era},keyword=corn:orth3]

\printbibliography[heading=bibintoc,title={Accounts of antiquarian work and of the early revival},keyword=corn:factrev]

\printbibliography[heading=bibintoc,title={(Critical) accounts of the later revival and
  contemporary use of Cornish},keyword=corn:critrev2]

\printbibliography[heading=bibintoc,title={Language policy},keyword=corn:pol]

\printbibliography[heading=bibintoc,title={Language technology},keyword=corn:tech]

\printbibliography[heading=bibintoc,title={For popular audiences},keyword=corn:pop]

\printbibliography[heading=bibintoc,title={Cornwall and Brittany},keyword=corn:bret]

\printbibliography[heading=bibintoc,title={A selection of non-language-focused
  works},keyword=corn:nonling]

\printbibliography[heading=bibintoc,title={Works I have not seen, but which are cited in earlier issues of \textit{The
  year's work in modern language studies}},keyword=corn:unsorted]

\end{document}
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