Columbia subject headings:
Ilocos Norte (Philippines)--Economic conditions.
Ilocos Norte (Philippines)--Social conditions.
Rural-urban migration--Philippines--Ilocos Norte.
Harvard subject headings:
Ilocos Norte (Philippines)--Economic conditions.
Ilocos Norte (Philippines)--Social conditions.
Rural-urban migration--Philippines--Ilocos Norte.
Princeton subject headings:
Ilocos Norte (Philippines)--Economic conditions.
Ilocos Norte (Philippines)--Social conditions.
Rural-urban migration--Philippines--Ilocos Norte.