Fibonacci Crossword

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Across
  1. 4. Fibonacci's first publication (5, 5)
  2. 5. First name of Emperor who recognised Fibonacci's services to Pisa
  3. 6. City of birth
  4. 8. The number system introduced by Fibonacci (5, 6)
  5. 9. Book published in 1220 (8, 10)
Down
  1. 1. Fibonacci's first name
  2. 2. Area where Fibonacci learnt about different number systems (13, 5)
  3. 3. Name of Ratio linked to Fibonacci sequence
  4. 7. Shape found in nature which can be generated by the Fibonacci sequence