Mammals of Pennsylvania
1966
Doutt, Kenneth J. |
Heppenstall, Caroline A. |
Guilday, John E. |
United States, Pennsylvania
Two studies of Tinicum Marsh, Delaware and Philadelphia counties, Pennsylvania
1970
McCormick, Jack |
Grant, Robert R. |
Ruth Patrick |
A list of the fishes recorded from Pennsylvania
Fowler, H. W. |
Hawks aloft : the story of Hawk Mountain
1960
Broun, Maurice |
Pennsylvania birdslife
1959
Luttringer, Leo A. |