Date::DateCalc 3.2 for Perl - Example date calculations based on the Gregorian calendar and the ISO/R 2015-1971. Includes program code. www.engelschall.com/u/sb/download/pkg/DateCalc-3.2.README
Week Numbering. - Example of usage of ISO 2015 week numbering system. www.parkwholesale.com/Growers_Calendar.htm
