Arizona
Tags
- thomaspollin
- Thomas
- Pollin
- USA
- Amérique
- Etats
- Unis
- Etats-Unis
- Vereinigten
- Staaten
- Vereinigten Staaten
- United
- States
- America
- United States
- United States of America
- summer institute
- energy
- environment
- students
- ITD
- Institute
- Training
- Development
- 2010
- panorama
- panoramique
- panoramic
- Arizona
- Grand
- Canyon
- National
- Park
- Grand Canyon National Park
- Grand Canyon
- National Park
- géologie
- geology
- strates
- stratum
- strata
- light
- shadow
- light and shadow
- red
- rouge
- rot
- steps
- Institute for Training and Development