Viennna Document 2011on Confidence- and Security-Building Measures,

…The participating States will exchange annually information on their military forces concerning the military organization, manpower and major weapon and equipment systems, as specified below, in the zone of application for confidence- and security-building measures (CSBMs). Participating States
which have no military forces to be reported will so inform all other participating States.

(10) The information will be provided in an agreed format to all other participating States not later than 15 December of each year. It will be valid as of 1 January of the following year and will include:
(10.1) 1. Information on the command organization of those military forces referred to under points 2 and 3 specifying the designation and subordination of all formations* and units** at each level of command down to and including brigade/regiment or equivalent level. The information will be
designed in such a way as to distinguish units from formations. Läs dokumentet