More Notable Birthdays on April 23: 1936 - Roy Orbison, Vernon, Texas, rocker, Pretty Woman 1899 - Vladimir Nabokov, born in St. Petersburg, Russia, novelist, Lolita, Ada 1858 - Max Planck, German physicist, Planck Constant, Nobel 1918 1791 - James Buchanan, Cove Gap, Pennsylvania, 15th U.S. president, 1857-61