00345nam a2200109 a 450000500170000010000300001724500680004726000220011530000220013749000580015963000180021720251203091522.0  aWorld Health organization  aUrban air pollution with particular reference to motor vechiles  aGenevabWHOc1969  a54 p.c22 cm.bPB  aWorld Health organisation technical report Seriesd46  aAir Pollution