学位服和学位帽租赁公司埃德和拉芬·斯克·洛夫则表示，校方这一禁令是因为过去曾发生过数起因抛帽造成的砸伤事件。
Gown and cap graduation rental company Ede and Ravenscroft said the ban was because a number of injuries had occurred in the past.
曾畿生， 王德芬。 现代儿科内分泌学——基础与临床。 上海： 上海科学技术文献出版社。 00： 。
Zeng JS, Wang DF. Contemporary pediatric endocrinology—Fundamentals and clinical practice. Shanghai: Shanghai Science and Technical Literature Press. 00: . Chinese.
应用推荐