000 00315 a2200133 4500
020 _a0749260475
082 _a621.382
_bOPE
090 _c13486
_d19847
245 _aBlock 5 Noise
260 _aNorthampton
_bOpen university
_c1990
_g1990
300 _a58p.
_c29cm
650 _aCommunications engineering
942 _cL
999 _c41817
_d41817