* [https://web.archive.org/web/20060323180316/http://www.pennamagazine.com/articolo.php?id=226] Articolo sui modelli tipo [[Duofold]] (relazione [[Parker]]-[[Omas]] solo affermata) | * [https://web.archive.org/web/20060323180316/http://www.pennamagazine.com/articolo.php?id=226] Articolo sui modelli tipo [[Duofold]] (relazione [[Parker]]-[[Omas]] solo affermata) |