Yes, I have. Wikipedia is good as it often has an entry for the unit in question and links to the unit's commanders. Sadly a photo is often lacking for the lesser known. Google is my last resort but can sometimes produce results when all else fails. But my experience is that after 3 or 4 searches, if nothing turns up, I am probably wasting my time.
If I cannot find any better sources, I will just call it a day. It would be nice to fill the gaps but is no big deal. Actually the France '40 artwork is so good that it needs no 'improvement' by me. The only thing I noticed that probably should be changed is the unit artwork for the German 254 Inf XX. It has the symbol for the 8th Inf XX, due no doubt to the similarity of commander names (Koch and Koch-Erpach). The corrected version is attached.
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