Fotis Jannidis wrote:

> our projects is trying to encode a story which was originally published in
> installments

[...]

I'd be hard pressed personally to think of a better scheme. But one thing
puzzles me and indicates I may have misunderstood something.

<milestone unit="installment"  n="2" id="install1" corresp="pinstall1"/>

Here your n value, as is standard practice with such elements, looks forward
to the following unit. But your ID values look back to the previous one. Is
this deliberate?

If I had to process markup of this kind, I'd prefer everything to point in
the same direction. I.e. Before the opening of the first installment

<milestone unit="installment"  n="1" id="install1" corresp="pinstall1"/>

Then, at the juncture you actually cite

<milestone unit="installment"  n="2" id="install2" corresp="pinstall2"/>

But then, as it says right at the start of that first instalment,  "nur war
es ihm manchmal unangenehm, daß er nicht auf dem Kopf gehn konnte", so
perhaps I've caught something from the subject matter.

Michael Beddow