From: Roozbeh Pourmader
Date: 2005-12-11
Subject: Numberings used in Iran
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These are the other item numbering systems we need for Persian as used
in Iran and Afghanistan:

1) Abjad-normal: This is simple. There is a fixed list of 28 strings,
and the numbering is not supported beyond that.

2) Abjad-numerical: This is like a the Greek system. There are different
strings for 1, 2, 3, ..., 9, 10, 20, ..., 90, 100, 200, ..., 900, and
1000. When counting, strings are concatenated, so 954 is "900"+"50"+"4".
This can only count until 1999.

3) Alphabetic: This is like Abjad-normal, but with 32 different strings.

4) Spelled numbers: This is a little hard. It's actually spelling each
number in letters, the equivalent of "one", "two", "three", ...

Of these, 1, 3, 4 are used in everyday documents (but never 1 and 3 in
the same document). Case 2 is only used when the publisher is somehow
old-style and the number of pages in the preamble or the items of a list
exceeds 28.

I can provide details is you are interested in implementing them.
Specifically, I have written down the exact rules for case 4 in an
algorithm-like thing, for numbers less than or equal to 10^{15}-1.
