WHO REGIONAL PUBLICATIONS EUROPEAN SER. ; No 31 547,800 Indoor air quality : biological contaminants : report on a WHO meeting Rautavaara 29 August - 2 September 1988 / World Health Organization, Regional Office for Europe Copenhagen. - Copenhagen : WHO, [1990]. - [6], 67 s. ; 24 cm (WHO Regional Publications European Ser. ISSN 0378-2255 ; No 31) ISBN 92-890-1122-X