Heller, W. J. 1. (1920). History of Northampton County [Pennsylvania] and the grand valley of the Lehigh: Under supervision and revision of William J. Heller, assisted by an advisory board of editors. Boston ; New York [etc.]: The Americn historical society.

Heller, William J. 1857-1920. History of Northampton County [Pennsylvania] and the Grand Valley of the Lehigh: Under Supervision and Revision of William J. Heller, Assisted By an Advisory Board of Editors. Boston ; New York [etc.]: The Americn historical society, 1920.

Heller, William J. 1857-1920. History of Northampton County [Pennsylvania] and the Grand Valley of the Lehigh: Under Supervision and Revision of William J. Heller, Assisted By an Advisory Board of Editors. Boston ; New York [etc.]: The Americn historical society, 1920.