I got 3 types of chickens, how to tell which ones are which?

[GimmeCake]

I have 3 pairs of 2 chickens (6 total) for laying eggs. I have Golden Laced Wyandottes, Dominiques, and Plymouth Rocks. I can at least tell the difference between the Golden Laced Wyandotts but the other two look almost the exact same. How would I tell which breed of chicken they are?

 

[ChickenCanoe]

The light dark contrast will be sharper in the barred rocks and more subtle in the dominikers.

 

[scratch'n'peck]

If they are Barred Plymouth Rocks they are mostly black with a white dot on the top of the head.

 

[gel2727]

Once they are older barred rocks have a single comb and Dominiques have a pea comb