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            | Abstract |  
            | We show that 
-umbilics
 with arbitrarily high indices exist. This implies that more than
 
-regularity
 is required to prove Loewner’s conjecture.
  |  
          
            | Keywords
                umbilic, curvature line, Carathéodory's conjecture,
                Loewner's conjecture
               |  
          
            | Mathematical Subject Classification 2010
                Primary: 53A05, 53C45
               
                Secondary: 57R42, 37C10, 53A30
               |  
          
            | Milestones
                Received: 7 August 2015
               
                Revised: 25 September 2016
               
                Accepted: 26 September 2016
               
                Published: 8 April 2017
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