@conference{Xu02, author = "H. Xu and R. A. Rutenbar and K. Sakallah", address = "San Diego (CA)", booktitle = "Proc. Int. Symp. on Physical Design", month = "apr", title = "{S}ub-{SAT}: {A} {F}ormulation for {R}elaxed {B}oolean {S}atisfiability with {A}pplications in {R}outing", year = "2002", }