000 00434 a2200097 4500
020 _a9261031412
920 _a92-61-03141-2
245 0 _aCCITT GAS 9 Handbook B :
_bCase Study on the Economic and Technical Aspects of the Transition of a Mixed (Analogue/Digital) National Network Moving to a Digital National Network /
_c.
710 2 _aInternational Telecommunication Union.
_eWydawca
_4pbl
260 _aGeneva :
_bITU,
_c1988.
300 _a260 s.:
_bil.;
_c30 cm.
999 _c1830
_d1830