Beginners Questions: how to add missing fields? Code lists? Travel Industry extensions?

["Joel Paula" <jp@scientia.pt>]

I have just started to learn and use UBL.

We have a ERP and want to produce Invoices using UBL. We will use it for
EDI.

1. According to my country's (Portugal - EU) laws, an electronic invoice
must provide all the information the paper based one would, in such a way
that either the customer or the EDI provider can produce a visualization
that reproduces it. There are several fields we show on the invoices, that
we can't find on the UBL 2.0 Invoice spec:
 a) Total Amount in words;
 b) Reference (title of the customer process/project, specific request, the
customer Reservation code, etc.). We can't use Notes for this, because we
also have a notes field.
 c) Specific instructions and/or warnings our customers (the supplier) may
have on the bottom of the document - that can span several paragraphs.
 d) A unique identification number that we use to identify any document,
regardless of its type or series.

 1.1 What do you think is our best strategy to add these fields?
 1.2 We thought about using the UBLExtension structure, but it seems to
require that we register somewhere and get an ExtensionAgencyID. Is this
true?
 1.3 If using UBLExtension is the way to go, where do we get a code list for
the ExtensionReason element?

2. Maybe someone else has needed the same fields, is there a central place
where we could find available and registered extensions that we could peek
from?

3. Do you know of some existing extensions/customizations for the travel
industry?


Thanks very much for your time.

All the best,
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Joel Paula                       :] www.scientia.pt [:

Scientia - Análise e Desenvolvimento de Software, Lda.
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