Keth (v)reit:

>I also think I asked plenty of (easy) questions.
>For example, I asked about the "tickets in their pockets" phenomenon
>and how it is handled in Iceland.

We are inclined to say "they have a ticket in their pocket".
The Krákumál, however, is hardly a good testimony since Ragnarr
is talking about himself in plural.

>My experience is that books on such abstract topics as for example
>mathematics, are among the best ways to learn a new language.

Interesting idea. Have you seen the ON-text "Algorismus"?
It is to be found in Hauksbók.

Regards,
Haukur