[1] HuTime - Time Information System ( 版) http://www.hutime.jp/
[2] Calendar List ( 版) http://datetime.hutime.org/calendar/
[3] hutime (HuTime Project) ( ()) https://github.com/hutime/
[4] HuTime Web API - Calendar Calculation, http://ap.hutime.org/cal/
[5] Microsoft Word - はじめに.doc - HuTimeReport_20120320.pdf, , http://www.h-gis.org/documents/papers/HuTimeReport_20120320.pdf