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-- TiagoTiago ( talk) 03:22, 27 October 2014 (UTC) reply

The red trajectory shown in the figure is right but not complete to easily understand the "right" to "left" turnaround. For this we take a point not in the center of the object "F" and we'll see in the bottom the two reflections of the path so that the image is returned "left" to "right".

-- AXRL ( talk) 20:36, 18 April 2017 (UTC) reply