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fraction of light and optic problems, though it is not restricted to this area \cite{Airy1,Airy2,Airy3}. It is even possible to transform a particular 
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\bibitem{Airy1} GB. Airy, 1111111111.
\bibitem{Airy2}  GB. Airy, 222222222.
\bibitem{Airy3}  GB. Airy, 3333333333.
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