Үүнийг мессежээр илгээх: Critical loads : concept and applications : proceedings of a conference held on 12-14 February 1992 in Grange-over-Sands / under the auspices of the British Ecological Society Industrial Ecology Group and the Natural Environment Research Council, and partly sponsored by the National Power/PowerGen Joint Environmental Programme ; edited by M. Hornung and R.A. Skeffington.