World Health organization. (2012). International travel and health. World Health Organization.
Chicagoスタイル(17版)引用形式World Health organization. International Travel and Health. Geneva, Switzerland: World Health Organization, 2012.
MLA(8版)引用形式World Health organization. International Travel and Health. World Health Organization, 2012.
警告: この引用は必ずしも正確ではありません.