Title from PDF file caption (viewed Sept. 29, 2008).
Mode of access: Internet at the FAA web site. Address as of 9/29/08: http://www.airweb.faa.gov/Regulatory%5Fand%5FGuidance%5FLibrary/rgAdvisoryCircular.nsf/0/ab1a49f0f72c9605862569ae006d3bba/$FILE/AC20-60.pdf; current access available via PURL.