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> > Well,as far as I know, "R",is the descendant of
> an Indo-european *s which was sondes in early
> Germanic,whence the Z spelling.R is taken so that the
> sound of the voiced sibilant undergoing the so
> called"rhotacism"could be indicated(textbooks describe
> it as something like the Czech r^).Besides I think
> there are instances of z written for a ts-like
> sound,found where a dental came to stand before a
> sibillant.

Hmmm, perhaps you could state that again in english?

Sorin