<?xml version="1.0"?>
<dblp>
<article key="journals/sLogica/SiegB98" mdate="2003-09-05">
<author>Wilfried Sieg</author>
<author>John Byrnes</author>
<title>Normal Natural Deduction Proofs (in classical logic).</title>
<pages>67-106</pages>
<year>1998</year>
<volume>60</volume>
<journal>Studia Logica</journal>
<number>1</number>
<url>db/journals/sLogica/sLogica60.html#SiegB98</url>
</article>
</dblp>
