000 00363 a2200121 4500
041 _aEn
082 _a333.7
_bGEM
245 _aGEMS/AIR methodology review Vol; 1
_bquality assurance in urban air quality monitoring
260 _c1994
_aNairobi
_bUnited Nations Environment Programme
_g1994
300 _c29 cm.
_avi,40 p.
650 _aENVIRONMENT-STUDY
942 _cSR
999 _c32717
_d34264