Bushtruk A. D. Passive methods of ecologic monitoring of natural complexes and geotechnical systems / A. D. Bushtruk, T. N. Bushtruk // Fundamental and applied problems of environmental protection. Vol. 1 : International conference, September, 12-16, 1995, Tomsk : abstracts. Tomsk, 1995. Vol. 1 : Physical-mathematical problems of environmental protection. P. 81