1 Subjects: “...thema EDItEUR::N History and Archaeology::NH History::NHT History: specific events and topics::NHTB...”

2 Subjects: “...;The Earth: natural history: general interest;Earth sciences;Environmental science, engineering...”

3 Subjects: “...Applied ecology;Conservation of the environment;The Earth: natural history: general interest...”

4 Subjects: “...::WNW The Earth: natural history: general interest...”

5 Subjects: “...history...”

6 Subjects: “...History / bicssc...”

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

8 Subjects: “...History of engineering & technology / bicssc...”

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

10 Subjects: “...History / bicssc...”

11 Subjects: “...::WNW The Earth: natural history: general interest...”

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

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

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

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