We define generalized Clifford parallelisms in PG(3, F) with the help of a quaternion skew field H over a field F of arbitrary characteristic. Moreover we give a geometric description of such parallelisms involving hyperbolic quadrics in projective spaces over suitable quadratic extensions of F .

In this paper we focus on the description of the automorphism group Γ of a Clifford-like parallelism on a 3-dimensional projective double space P(H F ), ℓ , r over a quaternion skew field H (with centre a field F of any characteristic). We compare Γ with the automorphism group Γ ℓ of the left parallelism ℓ , which is strictly related to Aut(H). We build up and discuss several examples showing that over certain quaternion skew fields it is possible to choose in such a way that Γ is either properly contained in Γ ℓ or coincides with Γ ℓ even though ℓ .Mathematics Subject Classification (2010): 51A15, 51J15

In this paper we introduce a class of left conjugacy closed loops which are also fibered in subsemigroups. We inspect the possibility to extend the semigroups of the fibration to commutative subgroups. Then we construct an example of such loops arising from a suitable selected subset of the set of all limit rotations of the hyperbolic plane over an euclidean field

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