private HashMap<Article, Location> findArticle(int articleID, int quantity)
	{
		HashMap<Article, Location> map = new HashMap<Article, Location>();

		for (Location location : locations) {

			for (int i = 0; i < location.getArticles().size() && quantity > 0; i++) {
				if (location.getArticles().get(i).getArticleID() == articleID) {
					map.put(location.getArticles().get(i), location);
					quantity--;
				}
			}
		}
		return map;
	}