Philippines. Environmental Management Bureau Department of Environment and Natural Resources. (1992). DENR Administrative Order no. 21, Series of 1992: Amending the revised rules and regulations implementing P.D. 1586 : environmental impact assessment system. Environmental Management Bureau, Department of Environment and Natural Resources.
Citace podle Chicago (17th ed.)Philippines. Environmental Management Bureau Department of Environment and Natural Resources. DENR Administrative Order No. 21, Series of 1992: Amending the Revised Rules and Regulations Implementing P.D. 1586 : Environmental Impact Assessment System. [Quezon City]: Environmental Management Bureau, Department of Environment and Natural Resources, 1992.
Citace podle MLA (9th ed.)Philippines. Environmental Management Bureau Department of Environment and Natural Resources. DENR Administrative Order No. 21, Series of 1992: Amending the Revised Rules and Regulations Implementing P.D. 1586 : Environmental Impact Assessment System. Environmental Management Bureau, Department of Environment and Natural Resources, 1992.