What is difference between Yao's "Garbled Circuit" and ther "Garbling Scheme" given by Bellare et al?
Yao's garbled circuits is a generic protocol for two-party computation, which uses garbled Boolean gates along with oblivious transfer in a specific two-round protocol with a generator and an evaluator. Bellare, Hoang, and Rogaway's paper proposes a security model for garbling schemes themselves (i.e. the operation performed on individual gates in Yao's protocol) along with some constructions of garbling schemes. 

Yao's protocol can be generalized to multiple parties, but those settings are usually better served by a protocol that generically supports many parties, such as GMW.