public boolean isRemoved() {
		if (isGroup()) {
			if (getLeafsDirect().size() == 0) {
				return false;
			}
			for (ILeaf leaf : getLeafsDirect()) {
				if (leaf.isRemoved() == false) {
					return false;
				}
			}
			for (IGroup g : getChildren()) {
				if (g.isRemoved() == false) {
					return false;
				}
			}
			return true;
		}
		return removed;
	}