Cheryl E. Praeger Ngo Dac Tuan Inequalities involving the Delandtsheer-Doyen parameters for finite line-transitive linear spaces. 38-62 2003 102 J. Comb. Theory, Ser. A 1 http://dx.doi.org/10.1016/S0097-3165(03)00012-8 db/journals/jct/jcta102.html#PraegerT03