Prof. Mortel:
Empty Quarter, near Najran, Saudi Arabia (2)
Prof. Mortel:
Empty Quarter, near Najran, Saudi Arabia (5)
Prof. Mortel:
Empty Quarter, near Najran, Saudi Arabia (6)
Prof. Mortel:
Empty Quarter, near Najran, Saudi Arabia (8)
Prof. Mortel:
Empty Quarter, near Najran, Saudi Arabia (9)
Prof. Mortel:
Empty Quarter, near Najran, Saudi Arabia (10)
Prof. Mortel:
In the Empty Quarter east of Najran, Saudi Arabia (2)
Prof. Mortel:
In the Empty Quarter east of Najran, Saudi Arabia (3)
Prof. Mortel:
In the Empty Quarter east of Najran, Saudi Arabia (4)
Prof. Mortel:
Empty Quarter, near Najran, Saudi Arabia (11)
Prof. Mortel:
Empty Quarter, near Najran, Saudi Arabia (1)
Prof. Mortel:
In the Empty Quarter east of Najran, Saudi Arabia (6)
Prof. Mortel:
In the Empty Quarter east of Najran, Saudi Arabia (7)
Prof. Mortel:
In the Empty Quarter east of Najran, Saudi Arabia (8)
Prof. Mortel:
In the Empty Quarter east of Najran, Saudi Arabia (9)
Prof. Mortel:
In the Empty Quarter east of Najran, Saudi Arabia (10)
Prof. Mortel:
In the Empty Quarter east of Najran, Saudi Arabia (11)
Prof. Mortel:
In the Empty Quarter east of Najran, Saudi Arabia (12)
Prof. Mortel:
In the Empty Quarter east of Najran, Saudi Arabia (13)
Prof. Mortel:
In the Empty Quarter east of Najran, Saudi Arabia (14)
Prof. Mortel:
In the Empty Quarter east of Najran, Saudi Arabia (15)
Prof. Mortel:
In the Empty Quarter east of Najran, Saudi Arabia (16)
Prof. Mortel:
In the Empty Quarter east of Najran, Saudi Arabia (17)
Prof. Mortel:
In the Empty Quarter east of Najran, Saudi Arabia (18)
Prof. Mortel:
In the Empty Quarter east of Najran, Saudi Arabia (19)
Prof. Mortel:
In the Empty Quarter east of Najran, Saudi Arabia (20)
Prof. Mortel:
In the Empty Quarter east of Najran, Saudi Arabia (21)
Prof. Mortel:
In the Empty Quarter east of Najran, Saudi Arabia (22)
Prof. Mortel:
In the Empty Quarter east of Najran, Saudi Arabia (23)
Prof. Mortel:
In the Empty Quarter east of Najran, Saudi Arabia (24)