Morris, W. E., & Burnside, T. (1839). Report of William E. Morris to Judge Burnside and others, of the survey for a rail road by the valley of the Bald Eagle: Demonstrating the practicability of passing the summit of the Alleghany Mountain ... : also, the letter of the Hon. Thomas Burnside to Nicholas Biddle upon the importance of the proposed communication : accompanied by a map and profile of the two routes surveyed. Philadelphia: Printed by John C. Clark ..

Morris, William E., and Thomas Burnside. Report of William E. Morris to Judge Burnside and Others, of the Survey for a Rail Road By the Valley of the Bald Eagle: Demonstrating the Practicability of Passing the Summit of the Alleghany Mountain ... : Also, the Letter of the Hon. Thomas Burnside to Nicholas Biddle Upon the Importance of the Proposed Communication : Accompanied By a Map and Profile of the Two Routes Surveyed. Philadelphia: Printed by John C. Clark ., 1839.

Morris, William E., and Thomas Burnside. Report of William E. Morris to Judge Burnside and Others, of the Survey for a Rail Road By the Valley of the Bald Eagle: Demonstrating the Practicability of Passing the Summit of the Alleghany Mountain ... : Also, the Letter of the Hon. Thomas Burnside to Nicholas Biddle Upon the Importance of the Proposed Communication : Accompanied By a Map and Profile of the Two Routes Surveyed. Philadelphia: Printed by John C. Clark ., 1839.