Telegraph and Mobile Services: Operations and Quality of Service – Operating methods for the international public telegram service .
"Operational provisions for the international public telegram
service"
is freely available as a PDF document here. It's status is listed
as "in force".
I keep on searching for Operational provisions for
the international public telegram service which is what I'm
familiar with as it was included in ship's radio station
publications.
Appendix B it was called I believe. For aural
and sounder reception.
This supersedes a similar description which had addressed
the Morse code in:
" Operational provisions for the international public
telegram service"
which had been an ITU Standardization recommendation,
specifically Division B of ITU-T Recommendation F.1, and
which has now been withdrawn.