TY  - MPI
TI  - The territorial growth of the United States
PY  - 1987///
CY  - Washington (DC)
PB  - National Geographic Society
KW  - Cartografia
KW  - 912=111
JG  - The United States
SP  - 1 mapa color.
PP  - Washington (DC)
PB  - National Geographic Society
ER  -