<?xml version="1.0"?>
<dblp>
<article key="journals/apal/AshCK97" mdate="2004-09-28">
<author>Christopher J. Ash</author>
<author>Peter Cholak</author>
<author>Julia F. Knight</author>
<title>Permitting, Forcing, and Copying of a Given Recursive Relation.</title>
<pages>219-236</pages>
<year>1997</year>
<volume>86</volume>
<journal>Ann. Pure Appl. Logic</journal>
<number>3</number>
<url>db/journals/apal/apal86.html#AshCK97</url>
</article>
</dblp>
