Does anyone know of a website or other source of information regarding the various sheet markings on the King Edward VIII stamp margins?
Stanley Gibbons does mention them though not even the latest 4 Kings covers the subject in any detail.
I have done Google searches with all the combinations of Great Britain King Edward VIII postage stamps, sheet markings, printers marks etc. without success.
Scans show some of the types of mark I mean.
Any help gratefully received.