Quelllinks
- https://mogdy.adhocracy.de/tag/apps4cities
- http://www.cs.tum.edu/index.php?id=273&tx_ttnews[calendarYear]=2009&tx_ttnews[calendarMonth]=7&tx_ttnews[mode]=1&tx_ttnews[startingPoint]=200&tx_ttnews[recursion]=250&tx_ttnews[pointer]=11&tx_ttnews[tt_news]=1021&tx_ttnews[backPid]=272&cHash=c51ff4c243fd56c32b22141c672cabee