00819cas|a2200241 i 450000500170000000800410001703500150005809000210007310000180009424500930011226000750020530000130028049000380029365000180033170000180034970000200036781000790038790700250046690200110049199800280050294500320053099900150056220260817161441.0011199s1976    enk u m rtt  00|  a1eng d  a.b10052525  aTE7bR63 no. 7311 aNelson, P. M.10aAcoustic performance of the M6 noise barriers /cby ..., P. G. Abbott and A. C. Salvidge  aCrowthorne, Berkshire :bTransport and Road Research Laboratory,c1976  a11, 5 p.1 aTRRL Laboratory report ;vno. 731 0aTraffic noise10aAbbott, P. G.10aSalvidge, A. C.2 aTransport and Road Research Laboratory.tTRRL Laboratory report ;vno. 731  a.b10052525bmngc cu  a150521  b1c951012dmea  fug0  lmngc aTE7bR63 no. 731-735  c1346d1346