I did respond a few minutes ago but I perhaps did not send it correctly? Not sure because I don't see it posted anywhere! Anyhow, this is more or less what I wrote. I would be grateful if you could acknowledge, so I know I have hit the right button! 

Thanks, Jill, for your interesting reply. I appreciate the time you took to provide me with this information. I will check out the sources you recommend.

Barry Clarke, Croydon/Edgware/Hove, now Sarasota, Florida