The blue print is marked, stained and foxed and has small holes and tears along one edge where it was once in an Argentine Air Force aerial bomb guide. The description is in Spanish but it is unclear if the blue print was made in Argentina or Italy, the age is assumed to be 1920/30s as some of the others prints/plans that I have from the same source are marked with these dates. It has some creases and has been folded and cut to fit the folder that it was stored in. N-4 is written in crayon/pencil on the back and front.