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J. De-beule and K. Metsch, Minimal blocking sets of size q 2 + 2 of Q(4, q), q an odd prime, do not exist. Finite Fields Appl

J. De-beule, A. Hoogewijs, and L. Storme, = 5,7, ACM SIGSAM Bulletin, vol.38, issue.3, pp.67-84, 2004.
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J. and D. Beule, Blocking sets and partial spreads in finite polar spaces, 2004.

M. Cimráková, S. De-winter, V. Fack, and L. Storme, On the smallest maximal partial ovoids and spreads of the generalized quadrangles W (q) and Q(4, q), J. Comb. Theory A, 2005.