@article {12771,
	title = {An algebraic theory of multiple clocks},
	journal = {CONCUR{\textquoteright}97: Concurrency Theory},
	year = {1997},
	month = {1997///},
	pages = {166 - 180},
	author = {Cleaveland, Rance and L\{\"u}ttgen,G. and Mendler,M.}
}
