The correspondence of Lord Acton and Richard Simpson - Acton, John Emerich Edward Dalberg Acton, Lord 1834-1902; Holland, James C. 1940-; Altholz, Josef L. 1933-2003; Simpson, Richard 1820-1876; McElrath, Damian (O.F.M.) 1928-2021 (Cambridge At the University Press, 1971)