i have found that as well but you also need to remember that boundaries have changed alot over the years. i am sure someone with more experienc will be able to give you more info. I also have trouble with oxfordshire.
I agree, I have trouble with both counties and wish there was more on the internet. Some of my ancestors lived in south Oxfordshire (and I don't think the boundaries there have changed much?) and seem to have moved back and forth across the Thames.
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