Hamburg´s modern architecture

Photos:
1. The Main Bus Station
(near Haupbahnhof)
Could you please think about "La Bandera"?

2. A only-one-wall building located near
Berlin Tor
(i believe belongs to the StadtWasser Hamburg, or maybe to HEW)

3. A "treppe" in the TUHH Library;
all the elements are reinforced crystal sheets