ウィリアムズポート (ペンシルベニア州)
1 2 3 Hunsinger, Lou Jr. Peter Herdic: Industrialist, Entrepreneur, Innovator. Williamsport Sun-Gazette.
↑ Hunsinger, Lou Jr. The Herdic Cab: A variation on a transportation theme. Williamsport Sun-Gazette.
1 2 Hill, Bob. Forests & Freedom: Forgotten Links In Pennsylvania's Underground Railroad. Pennsylvania Department of Conservation and Natural Resources.
↑ Hunsinger, Lou Jr. Daniel Hughes: Giant of Freedom Road. Williamsport Sun-Gazette.
1 2 Auken, Robin Van. Timeline. News of Yesteryear, Historic Pennsylvania & Historic Williamsport.
1 2 Williamsport, Pennsylvania. newPA.com.
1 2 Detrow, Scott. Natural Gas Fuels Economy In Pennsylvania. NPR. 2010年9月21日.
1 2 Historical Weather for Williamsport, Pennsylvania, United States of America.