Because Tony Augarde was quoted as saying some very strange about ten-squares in a British national newspaper. I decided to see how he tackled the subject in the Oxford Guide to Word Games (2nd edition, 2003), a review of which appears in W03-194. The newspaper had quoted an expert as estimating that 900 9-squares had been compiled: the book makes it clear that this was Dmitri Borgmann, so the estimate has long been overtaken by events.
"The Ascent of Man,"
Word Ways: Vol. 39
, Article 25.
Available at: http://digitalcommons.butler.edu/wordways/vol39/iss2/25