The "Concise" lists the GB ones after the security Machins.
I know the Norvic site also lists them as issued. http://www.norphil.co.uk/
Not sure of other countries but imagine they would list them in specialised catalogues.
Just to add that on the Norphil site there is a downloadable checklist for the Post and Go. It can be found under "Links" on the right hand side.
http://postandgochecklist.yolasite.com
Is there a catalog for the post & go stamps which would include ID numbers and values.
I know that they are issued in both Great Britain and Ireland but they are not included in Scott's.
I don't see any referance to them on Stamp World. I Have found some info on CollectGBStamps.uk and on norphil.co.uk
re: Post & Go Stamps
The "Concise" lists the GB ones after the security Machins.
I know the Norvic site also lists them as issued. http://www.norphil.co.uk/
Not sure of other countries but imagine they would list them in specialised catalogues.
re: Post & Go Stamps
Just to add that on the Norphil site there is a downloadable checklist for the Post and Go. It can be found under "Links" on the right hand side.
re: Post & Go Stamps
http://postandgochecklist.yolasite.com