A generalization of ray tracing in symmetric Gradient-Index media by Fermat's ray invariant
2009 ◽
Vol 26
(11)
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pp. 2035
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1998 ◽
Vol 37
(Part 1, No. 6B)
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pp. 3638-3642
1992 ◽
Vol 9
(2)
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pp. 331
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