1 Subjects: “...economic profit...”

2 Subjects: “...engineering economics...”

3 Subjects: “...History of engineering and technology / bicssc...”

4 Subjects: “...economic evaluation...”

5 Subjects: “...integrated ecological-economic modeling...”

6 Subjects: “...economic sustainability...”

7 Subjects: “...economic analyses...”

8 Subjects: “...internal combustion engines-generator...”

9 Subjects: “...traditional rice economics...”

10 Subjects: “...socio-economic impacts...”

11 Subjects: “...economic efficiency...”

12 Subjects: “...economic benefits...”

13 Subjects: “...Development economics & emerging economies / bicssc...”

14 Subjects: “...History of engineering and technology / bicssc...”

15 Subjects: “...History of engineering and technology / bicssc...”

16 Subjects: “...Technology, engineering, agriculture / bicssc...”

17 Subjects: “...Technology, engineering, agriculture / bicssc...”