On the equivalence of Playfair’s axiom to the parallel postulate Elizabeth T. BrownEmily CastnerA. J. Vargas OriginalPaper 01 August 2019 Article: 42
Certain results on almost contact pseudo-metric manifolds V. VenkateshaDevaraja Mallesha NaikMukut Mani Tripathi OriginalPaper 16 July 2019 Article: 41
Radial expansion preserves hyperbolic convexity and radial contraction preserves spherical convexity Dhruv KohliJeffrey M. Rabin OriginalPaper 13 July 2019 Article: 40
Ceva’s and Menelaus’ theorems in projective-metric spaces Árpád Kurusa OriginalPaper Open access 12 July 2019 Article: 39
A sufficient condition for a polyhedron to be rigid Victor Alexandrov OriginalPaper 17 June 2019 Article: 38
Affine semipolar spaces Krzysztof PrażmowskiMariusz Żynel OriginalPaper Open access 14 June 2019 Article: 37
An algebraic characterization of properly congruent-like quadrilaterals Giuseppina AnatrielloFrancesco LaudanoGiovanni Vincenzi OriginalPaper 12 June 2019 Article: 36
A characterization of the known finite Minkowski planes in terms of Klein–Kroll types with respect to \(\mathcal {G}\)-translations Günter F. Steinke OriginalPaper 07 June 2019 Article: 35
\(\eta \)-Ricci solitons in \(\epsilon \)-Kenmotsu manifolds Abdul HaseebUday Chand De OriginalPaper 06 June 2019 Article: 34
Center of mass and Kähler structures Scott O. WilsonMahmoud Zeinalian OriginalPaper 01 June 2019 Article: 33
On the medians of a triangle in two-point homogeneous spaces Boumediene Et-Taoui OriginalPaper 31 May 2019 Article: 32
The geometry of Gauss map and shape operator in simply isotropic and pseudo-isotropic spaces Luiz C. B. da Silva OriginalPaper 30 May 2019 Article: 31
Non-existence of \(*\)-Ricci solitons on \((\kappa ,\mu )\)-almost cosymplectic manifolds Xinxin Dai OriginalPaper 29 May 2019 Article: 30
On constructions of surfaces using a geodesic in Lie group Zuhal Kucukarslan YuzbasDae Won Yoon OriginalPaper 28 May 2019 Article: 29
A new approach on constant angle surfaces in the special linear group Thiago Mendonça OriginalPaper 25 May 2019 Article: 28
Developable surfaces along frontal curves on embedded surfaces Shun’ichi HondaShyuichi IzumiyaMasatomo Takahashi OriginalPaper 24 May 2019 Article: 27
On the existence of a closed, embedded, rotational \(\lambda \)-hypersurface John Ross OriginalPaper 15 May 2019 Article: 26
A perimeter-based angle measure in generalized Minkowski planes Alina Obst OriginalPaper 08 May 2019 Article: 25
The Hajja–Martini inequality in a weak absolute geometry Davit HarutyunyanAram NazaryanVictor Pambuccian OriginalPaper 08 May 2019 Article: 24
\(\mathcal {D}\)-Homothetic deformation on almost contact B-metric manifolds Şenay Bulut OriginalPaper 03 May 2019 Article: 23
Semi-Riemannian hypersurfaces in \(\mathbb {L}^{n+1}\) with a totally geodesic foliation of codimension one S. M. B. KashaniM. J. VanaeiS. M. Yaghoobi OriginalPaper 26 April 2019 Article: 22
Two characterizations of the family of secant lines of an ovoid of PG(3, \({\varvec{q}}\)) Vito Napolitano OriginalPaper 24 April 2019 Article: 21
Translation surfaces with non-zero constant mean curvature in Euclidean space Thomas Hasanis OriginalPaper 08 April 2019 Article: 20
A characterization of the set of internal points of a conic in PG(2,q), q odd Stefano InnamoratiFulvio Zuanni OriginalPaper 02 April 2019 Article: 19
