Columbia subject headings:
Ecological houses.
Green roofs (Gardening)--Design and construction.
Vertical gardening.
Harvard subject headings:
Green roofs (Gardening)
Green roofs (Gardening)--Pictorial works.
Landscape gardening
Urban landscape architecture
Vertical gardening
Vertical gardening--Pictorial works.
Princeton subject headings:
Ecological houses.
Green roofs (Gardening)--Design and construction.
Vertical gardening.