1. Graduate School of Economics, Soka University, Hachioji, Tokyo, Japan
2. Faculty of Business Administration, Soka University, Hachioji, Tokyo, Japan
3. Faculty of Economics, Soka University, Hachioji, Tokyo, Japan
4. Faculty of Nursing, Soka University, Hachioji, Tokyo, Japan
5. Faculty of Science and Engineering, Soka University, Hachioji, Tokyo, Japan
6. College of Agriculture and Environmental Sciences, Bahir Dar University, Bahir Dar, Ethiopia
7. Faculty of Agriculture, Dalhousie University, Truro, Nova Scotia, Canada