Comments by the authors on Volume 8, article
R29 (August 25, 2003):
In the above paper, the theorem that at least (n-1)/2 queens are
required to dominate the n by n chessboard was
attributed to P. H. Spencer, in .
A proof of this result appeared in the earlier work .
- E. J. Cockayne, Chessboard
domination problems, Discrete Math.
86 (1990), 13--20.
- V. Raghavan and S. M. Venkatesan, On bounds for a covering
Inform. Process. Lett. 25 (1987), 281--284.