Town Twinning and German City Growth
研究了二战后德国城镇结对对城市增长的影响，发现结对城市增长更快，尤其是与法国结对及结对数量与强度起正向作用，对大城市影响更显著。
Brakman S., Garretsen H. and Oumer A. Town twinning and German city growth, Regional Studies. After the Second World War, town twinning became popular, notably in Germany. This was mainly a reaction to the war experience, and it was initially aimed at creating renewed international understanding and cooperation between former enemies. It also reduced transaction costs. The results show that counties that engage in town twinning grow faster than cities that do not have twinning partners. In particular, both the number and the intensity of twinning relations as well as town twinning with French cities positively affect city growth. Positive population growth effects of town twinning are also mostly confined to the larger German cities.