「注释」

① Sister Cities International, “Membership”, see http:// sister- cities. org/ membership, last retrieved on May 4, 2017.

Council of European Municipalities and Regions, “Table Showing the Number of Twinnings in the Wider Europe in 2010”, see http:// www. twinning. org/ uploads/assets/ news/ Number%20of%20twinnings%20in%20Europe%20in%20 2010. pdf, last retrieved on May 4, 2017.