1) John Hervey, 2nd Baron Hervey, called Lord Hervey (1696-1743) wrote Memoirs of the reign of George the Second.
2) John G. (Gaines) Hervey (b. 1900) wrote Federal Textbook on Citizenship....
3) Hervey, John (1870-1947) wrote The American Trotter.
4) Hervey, John (f. 1990) wrote Collector's guide to cartoon and promotional drinking glasses.