Double breasted or center fastening?

[rocktupac]

Looking at the pteruges can give an idea. If there are two rows on the front and only one at the rear then it is double-breasted. How many illustrations show pteruges like this?

In nearly 1,000 images depicting the 'tube-and-yoke' I'm not sure I have seen a cuirass like the one you describe with a double row in front and a single row in back. I'm almost certain I've never seen one. Do you have an example?