(1990). Diseases of the digestive system. World health organization.
芝加哥风格引文Diseases of the Digestive System. Ginebra: World health organization, 1990.
MLA引文Diseases of the Digestive System. World health organization, 1990.
警告:这些引文格式不一定是100%准确.
(1990). Diseases of the digestive system. World health organization.
芝加哥风格引文Diseases of the Digestive System. Ginebra: World health organization, 1990.
MLA引文Diseases of the Digestive System. World health organization, 1990.