Draper, N.R. (1963). "Does Age Affect Master Chess?". Journal of the Royal Statistical Society, Series A. 126 (1): 120–127. doi:10.2307/2982450. JSTOR2982450.
Silman, J. "Wilhelm Steinitz". Jeremy Silman. Archived from the original on 19 June 2008. Retrieved 17 June 2008. Has several examples of Steinitz testing his theories in top-class play.
Draper, N.R. (1963). "Does Age Affect Master Chess?". Journal of the Royal Statistical Society, Series A. 126 (1): 120–127. doi:10.2307/2982450. JSTOR2982450.
kwabc.org
For a picture of his grave, see "At the grave of Adolf Anderssen". Ken Whyld Association. Archived from the original on 15 February 2012. Retrieved 19 November 2008. The source for the date of the reburying is SchachReport, no. 9/1995, p.74
Silman, J. "Wilhelm Steinitz". Jeremy Silman. Archived from the original on 19 June 2008. Retrieved 17 June 2008. Has several examples of Steinitz testing his theories in top-class play.
For a picture of his grave, see "At the grave of Adolf Anderssen". Ken Whyld Association. Archived from the original on 15 February 2012. Retrieved 19 November 2008. The source for the date of the reburying is SchachReport, no. 9/1995, p.74