<bibliography>
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  <author>Jean Berstel</author>
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  <year>1993</year>
  <title>A geometric proof of the enumeration formula for Sturmian words</title>
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  <year>1997</year>
  <title>Complexit&#233; et facteurs sp&#233;ciaux</title>
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  <volume>4</volume>
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  <pages>67&#8211;88</pages>
  <url>http://projecteuclid.org/getRecord?id=euclid.bbms/1105730624</url>
  <note>Journ&#233;es Montoises (Mons, 1994)</note>
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  <author>E. P. Lipatov</author>
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 <citation type="book" key="Lothaire2002">
  <author>M. Lothaire</author>
  <year>2002</year>
  <title>Algebraic combinatorics on words</title>
  <series>Encyclopedia of Mathematics and its Applications</series>
  <volume>90</volume>
  <publisher>Cambridge University Press</publisher>
  <address>Cambridge</address>
  <note>Chapter 3, Sturmian Words (by Jean Berstel and Patrice S&#233;&#233;bold)</note>
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 <citation type="article" key="Mignosi1991">
  <author>Filippo Mignosi</author>
  <year>1991</year>
  <title>On the number of factors of Sturmian words</title>
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  <number>1, Algorithms Automat. Complexity Games</number>
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 <citation type="inproceedings" key="MonteilDGCI2011">
  <author>Thierry Monteil</author>
  <year>2011</year>
  <title>Another Definition for Digital Tangents</title>
  <booktitle>DGCI</booktitle>
  <series>Lecture Notes in Computer Science</series>
  <volume>6607</volume>
  <pages>95&#8211;103</pages>
  <doi>10.1007/978-3-642-19867-0_8</doi>
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  <author>N. Pytheas Fogg</author>
  <year>2002</year>
  <title>Substitutions in dynamics, arithmetics and combinatorics</title>
  <series>Lecture Notes in Mathematics</series>
  <volume>1794</volume>
  <publisher>Springer-Verlag</publisher>
  <address>Berlin</address>
  <doi>10.1007/b13861</doi>
  <note>Chapter 6, Sturmian Sequences (by Pierre Arnoux)</note>
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</bibliography>
