Nature of defect
Description of issue
The reference to the ZIP file format gives the URL ftp://ftp.uu.net/pub/archiving/zip/doc/appnote-970311-iz.zip
At the time of writing (2009-10-11) this resource, hosted on a commercial web site owned by a US company, is password-protected.
It is imperative that referenced resources are both authoritative and accessible; this is neither.
Reference the variant of the ZIP file format specification required by this Standard in an authoritative and accessible manner.