Just came across this in an Amazon.com review of a book called "Twas only an Irishman's dream":

Dr. Williams takes what may at first seem like a narrow subject---Irish-American song lyrics---and uses it to tell not only the story of the Irish in America, but of American popular culture as well. This book is full of revelations. Readers unfamiliar with the subject matter will be surprised to learn that not too long ago in our history, Irish-American music and popular culture were practically synonymous. Others with a more sophisticated knowledge of Irish American history will be delighted at all sorts of surprises---e.g., "The Cobbler" and "The Real Old Mountain Dew," two songs popularized by the Clancy Brothers and Tommy Maken early in their career, were actually written by Ned Harrigan, a 3rd-generation Irish-American New Yorker.

Regards