@InProceedings{ce-tnpcs-06l
,   author =     "Colin de Verdi{\`e}re, {\'E}ric and Erickson, Jeff"
,   title =      "Tightening non-simple paths and cycles on surfaces"
,   booktitle =  "Proceedings of the 17th ACM-SIAM Symposium on Discrete Algorithms (SODA)"
,   year =       2006
,   month =      jan
,   pages =      "192--201"
}