Columbia subject headings:
Birth control--Cross-cultural studies--Statistics.
Birth control--Cross-cultural studies.
Contraception--Cross-cultural studies--Statistics.
Contraception--Cross-cultural studies.
Harvard subject headings:
Birth control--Cross-cultural studies--Statistics.
Birth control--Cross-cultural studies.
Contraception--Cross-cultural studies--Statistics.
Contraception--Cross-cultural studies.
Contraception--Statistics.
Population.
Princeton subject headings:
Birth control--Statistics.
Contraception--Statistics.