:: I think the problem might be the unnecessarily mathematical description "up to an additional 24−N nautical miles beyond the territorial sea, where the territorial sea is N nautical miles wide, N≤12".  If you were just skimming over the article, it would be easy to misread that the 24-N as 24N (i.e. 24 nautical miles).  Unless anyone objects, I'll change this to a more plain-English description, such as "A Contiguous Zone extends from the limit of the territorial sea, up to a distance of 24 nautical miles from the baseline", possibly also adding "In cases where the country in question has claimed less than 12nm for its territorial waters, its contiguous zone may therefore be more than 12nm wide".
 Unless it has already been added (and I have just missed it), it needs to be mentioned that when territorial/contiguous zones belonging to different countries intersect, then the median line is taken as the boundary.