. 2014 Jun 17;2014:836375. doi: 10.1155/2014/836375
Copyright © 2014 Mostofa Kamal Nasir et al.
This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Figure 4.
Three-tier open traffic control system.