CJ Colbourn, AD Forbes, MJ Grannell… - the electronic journal …, 2010 - combinatorics.org
Abstract Properties of the 11$\, $084 $\, $874 $\, $829 Steiner triple systems of order 19 are
examined. In particular, there is exactly one 5-sparse, but no 6-sparse, STS (19); there is …