TY  - BOOK
AU  - Van Valkenburg, Samuel
AU  - Erickson, Franklin C
TI  - Elements of political geography
T2  - Prentice-hall geography series
AV  - JC 319 V35
PY  - 1946///
CY  - New York
PB  - Prentice-Hall.
KW  - Geografía
KW  - Política mundial
KW  - Fronteras
KW  - Antropogeografía
ER  -