1. 〈http://www.hitachi-aloka.co.jp/english/products/data/radiation-002-TCS-171172〉.
2. 〈http://www.hitachi-aloka.co.jp/english/products/data/radiation-002-ICS-331〉.
3. 〈http://www.nmea.org/〉.
4. 〈http://www.dropbox.com〉.
5. 〈http://www.google.com/earth/index.html〉.