In the page of Packagejava.util.zip,
( http://docs.oracle.com/javase/7/docs/api/java/util/zip/package-summary.html)
there is a link to "Info-ZIP Application Note 970311", but this is incorrect.
(ftp://ftp.uu.net/pub/archiving/zip/doc/appnote-970311-iz.zip)

NOTE:
The correct URL seems http://info-zip.org/doc/appnote-19970311-iz.zip