TY  - BOOK
AU  - Powel,John Wesley
TI  - The exploration of the Colorado River and its canyons
T2  - The penguin natura library
AV  - F788 P68
PY  - 1961///
CY  - New York
PB  - Dover
KW  - Powel, John Wesley, 
N1  - Colección California mexicana Ascension y Miguel LeónPortilla
ER  -