Clemens family (Abraham Clemens, ca. 1718-1785).
- The ancestry of Samuel Clemens : grandfather of Mark Twain / by Raymond Martin Bell ; with an introd. by Ralph Gregory.
Clemens family (Anthony Clemens, fl. 1610).
- The Clemens family chronology, 1610-1912. William M. Clemens.
Clemens family (Gerhart Clemens, 1680-1744 or 5)
- The Strassburger family and allied families of Pennsylvania; being the ancestry of Jacob Andrew Strassburger, esquire, of Montgomery county, Pennsylvania, by his son Ralph Beaver Strassburger.
Clemens family (Jeffrey Clement, d. 1609).
- Mark Twain's kinfolks. Compiled by P. O. Selby.
Clemens family (Richard Clements, ca. 1506-1571).
- The ancestry of Samuel Clemens, grandfather of Mark Twain / by Raymond Martin Bell ; with an introduction by Ralph Gregory.