2. Environmental health perspectives: EHP Research Triangle Park, N.C. : National Institute of Environmental Health Sciences, National Institutes of Health, Dept. of Health, Education and Welfare, 1972- ECON336
3. Harvard business review Boston Graduate School of Business Administration, Harvard University. BUS552 BUS100 BUS130 BUS200 BUS304 BUS305 BUS408 BUS424 BUS460
