摘要
本文给出了一个有限Ｍ－ＳＣＡＢ是Ｂｕｉｌｄｉｎｇ的充要条件及一个有限Ｍ－ＳＣＡＢ的万有覆盖是Ｂｕｉｌｄｉｎｇ的充要条件
In this paper, We provide a necessary and sufficient condition for a finite M SCAB being a buildig and a necessary and sufficient condition for universal covering of a finite M SCAB being a buildig.
