Regarda fonte per Cuatro de Klein

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! style="background:#FBFBE0;"|2
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! style="background:#FBFBE0;"|1 || 1 || 2 || 3 || 4
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! style="background:#FBFBE0;"|2 || 2 || 1 || 4 || 3
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! style="background:#FBFBE0;"|3 || 3 || 4 || 1 || 2
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! style="background:#FBFBE0;"|4 || 4 || 3 || 2 || 1
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([[deutx (lingua)|orijinal]] Kleinsche Vierergruppe)
<gallery>Fix:Felix_Christian_Klein.jpg|fundor de metre spasial «Cayley-Klein»</gallery>
==Lias ==
<gallery>File:Eccentricity.svg|plana de [[Euclide]]
</gallery>