Thank you very much Patrick, I have found this mailing list - https://listserv.brown.edu/archives/cgi-bin/wa?A0=TEI-L - and subscribed to it. I will post there.
Anyway, here is my first attempt.
Amir

On Tue, Aug 14, 2018 at 2:04 AM, Patrick McAllister <patrick.mcallister@oeaw.ac.at> wrote:
On Sat, Aug 11 2018, Amir Simantov wrote:

> Hello.
>
> I am looking for either a UML class diagram or an object relation diagram
> (ORD) of either:
>
>    1. The "Manuscript Description"
>    http://www.tei-c.org/release/doc/tei-p5-doc/en/html/MS.html
>
>    Or, at least, to:
>
>    2. "The Manuscript Identifier" section inside it
>    http://www.tei-c.org/release/doc/tei-p5-doc/en/html/MS.html#msid
>
> Can anybody help here?

You could try to use the method for creating a graph described here:

https://williamjturkel.net/2013/09/16/simple-xml-parsing-and-graph-visualization-with-command-line-tools-in-linux/

This will work only for a concrete example XML document, however, and so
there’s no guarantee that all combinations of the elements allowed or
required will be visible in the diagram, I think.  What you’re asking
should properly be derived from the specification.  Since the ODDs are
XML documents, maybe one could adopt the method above?

You could consider posting this also to the general TEI mailing group
since it doesn’t seem specific to Indic texts as such.

Best wishes,

--
Patrick McAllister

Email: patrick.mcallister@oeaw.ac.at
Phone: + 43 1 51581 6423

Institute for the Cultural and Intellectual History of Asia (IKGA)
Austrian Academy of Sciences
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1020 Vienna, Austria

http://www.ikga.oeaw.ac.at/