A 1-factorization (or parallelism) of the complete graph with loops \documentclass[12pt]{minimal}
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\begin{document}$$(P, \mathcal{E}, ||)$$\end{document} is called polar if each 1-factor (parallel class) contains exactly one loop and for any three distinct vertices x1, x2, x3, if {x1} and {x2, x3} belong to a 1-factor then the same holds for any permutation of the set {1, 2, 3}. To a polar graph \documentclass[12pt]{minimal}
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\begin{document}$$ (P, \mathcal{E}, ||)$$\end{document} there corresponds a polar involution set \documentclass[12pt]{minimal}
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\begin{document}$$ (P, \mathcal{I})$$\end{document}, an idempotent totally symmetric quasigroup (P, *), a commutative, weak inverse property loop (P, + ) of exponent 3 and a Steiner triple system \documentclass[12pt]{minimal}
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\begin{document}$$ (P, \mathcal{B})$$\end{document}.