@InProceedings{ce-tnpcs-10l
,   author =     "Colin de Verdi{\`e}re, {\'E}ric and Erickson, Jeff"
,   title =      "Tightening nonsimple paths and cycles on surfaces"
,   journal = "SIAM Journal on Computing"
,   year = 2010
,   volume = 39
, number = 8
, pages = "3784--3813"
,   note =  "A conference version appeared in \emph{Proceedings of the 17th ACM-SIAM Symposium on Discrete Algorithms (SODA)} 2006, 192--201."
}