National Environment Commission. Strategy for air quality assessment and management in Bhutan / - Thimphu, Bhutan : National Environment Commission, 2010. - 72 p. : ill. (some col. maps) ; 21 cm. ISBN: NA LC Class. No.: GD00482-GD00483 Dewey Class. No.: A5.5 / NEC Gov. Doc. Class. No.: A5.4