shilgia, you'll be glad to know that the Dutch wikipedia entry on karton says this:
Tussen 1870 en 1970 werd het (i.e. strokarton) met name geproduceerd in de noordelijke provincies Groningen en Friesland en in de aangrenzende Duitse Provincies (waaronder in de stad Leer)
And do you know this?
I was wondering the same about mask (and forgot to ask.)
The OED has "The mesh of a net" for mask, maybe that is it. (Since the list also includes cordage.)
Drs. P is great, and that song is, too. It's too bad you don't speak Dutch, Vinny, because the lyrics are very good.
The dates 1870-1970 did not prevent strokarton from showing up for Groningen and Friesland in school geography books well into the 1980s.