Papua New Guinea & United Nations Environment Programme. (1986). Environmental management in Papua New Guinea. [s.n.].
芝加哥风格引文Papua New Guinea 与 United Nations Environment Programme. Environmental Management in Papua New Guinea. [S.l.]: [s.n.], 1986.
MLA引文Papua New Guinea 与 United Nations Environment Programme. Environmental Management in Papua New Guinea. [s.n.], 1986.
警告：这些引文格式不一定是100％准确.