From a letter of Tolstoy to the Federation of Single Tax Leagues in Austria, October 20, 1908:
"The supposed right of landed property now lies at the foundation not only of economic misery, but also of political disorder, and, above all, the deprivation of the people. The wealthy ruling classes, foreseeing the loss of the advantages of their position inevitable with the solution of the problem, are endeavouring, with all their power, to postpone as long as possible its solution. But as 50 years ago the time came for the abolition of man's supposed right of property over man, so the time has come for the abolition of the supposed right of property in land, which affords the possibility of appropriating other people's labour."
If you can find the whole text of the letter, please point me to it.