TY - JOUR AU - Krzysztof Petelczyc AU - Krzysztof Prażmowski AU - Mariusz Żynel TI - Geometry of the parallelism in polar spine spaces and their line reducts JO - Ars Mathematica Contemporanea PY - 2021 SP - 151 EP - 170 VL - 20 IS - 1 PB - mathdoc UR - http://geodesic.mathdoc.fr/articles/10.26493/1855-3974.2201.b65/ DO - 10.26493/1855-3974.2201.b65 LA - en ID - 10_26493_1855_3974_2201_b65 ER -