Criterion for purely elastic Taylor-Couette instability in the flows of shear-banding fluidsM. A. Fardin, T. J. Ober, C. Gay, G. Grégoire, G. H. McKinley and S. LerougeEPL, 96 4 (2011) 44004DOI: https://doi.org/10.1209/0295-5075/96/44004