Barwick, S.G.Hui, A.M.W.Jackson, W.A.Schillewaert, J.2020-02-162020-02-162020Designs, Codes and Cryptography, 2020; 88(1):33-390925-10221573-7586http://hdl.handle.net/2440/123368Let H be a non-empty set of hyperplanes in PG(4,q), q even, such that every point of PG(4,q) lies in either 0, 1/2q³ or 1/2(q³+q²²) hyperplanes of H, and every plane of PG(4,q) lies in 0 or at least 1/2q hyperplanes of H. Then H is the set of all hyperplanes which meet a given non-singular quadric Q(4, q) in a hyperbolic quadric.en© Springer Science+Business Media, LLC, part of Springer Nature 2019Projective geometry; quadrics; hyperplanesJournal article003013274710.1007/s10623-019-00669-y0005117639000032-s2.0-85070107651477480Barwick, S.G. [0000-0001-9492-0323]Jackson, W.A. [0000-0002-0894-0916]