Vitomatic serial numbers?

[nparsons13]

Where do I look to find the serial numbers of my Vitomatics II and IIa? Or do they not have serial numbers? Surely such a popular, well-made rangefinder rated a SN, but I've searched both of them inside and out and can't find a stamped or painted number anywhere. Could it be under the top cover? I haven't looked there.

 

[nparsons13]

Found it! Around the outside of the lens filter ring. Thanks to Daniel Jiménez Chocrón in "From the Focal Plane to Infinity," https://sites.google.com/site/fromthefocalplanetoinfinity/vitomatic2b.