TY - BOOK AU - Gupta, S.P. Das TI - Environmental issues for the 21st century SN - 8170998735 U1 - 363.7 PY - 2003/// CY - New Delhi PB - Mittal Publications KW - Social services; association KW - Other social problems & services KW - Environmental Science KW - Environmental issues -- 21st Century KW - Integrated Pollution KW - Biological Air Pollution ER -