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2. Intercept Research Corporation - Brian Gard, Inc., 1984. Publishers Paper Company Recycling Attitudes and Behavior. Lake Oswego, OR, 124 pp.
3. The public's opinion of recycling;Anonymous;Resour. Recycl.,1982
4. Recycling behavior and motivation in the general Seattle population and the SORT area residents;City of Seattle,1979
5. Exploring the difference between recyclers and non-recyclers: the role of information;De Young;J. Environm. Syst.,1988