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Fig. 5


Grale models employing all multiple image systems of Table 1 detailed in Sect. 4.2.1(left), and only system 1 of Table 1 detailed in Sect. 4.2.2 (right). The critical curves for zs = 1.675 determined by the sign change of the determinant of the magnification matrix are marked in red, the multiple images are marked in blue.

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