Nicko. Today I was looking through the content page of a 1939 edition of AP 1208 – Airworthiness Handbook for Civil Aircraft. Volume 1, “Design”, has a leaflet G-3 – Plywood Edges within it. It was I think a new item added that year. It could be of interest, but unfortunately I don’t have a copy of the actual document. 

I suspect the leaflet may also feature in the AID leaflets as they (I think) were the tablets from which AP 1208 took its source of information.