Counting set covers and split graphs. Royle, Gordon F. — 2000 Journal of Integer Sequences [electronic only]
The rank of a cograph. Royle, Gordon F. — 2003 The Electronic Journal of Combinatorics [electronic only]
Graphs with chromatic roots in the interval ( 1 , 2 ) . Royle, Gordon F. — 2007 The Electronic Journal of Combinatorics [electronic only]
Acyclic digraphs and eigenvalues of ( 0 , 1 ) -matrices. McKay, Brendan D.; Oggier, Frédérique E.; Royle, Gordon F.; Sloane, N.J.A.; Wanless, Ian M.; Wilf, Herbert S. — 2004 Journal of Integer Sequences [electronic only]