Weights of 151 Species of Pennsylvania Birds Analyzed by Month, Age, and Sex.
Clench, Mary H.; Leberman, Robert C.
The Birds of Pennsylvania
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Birder's Guide to Pennsylvania (Birder's Guide Ser.)
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Relationships Among Body Mass, Fat, Wing Length, Age, and Sex for 170 Species of Birds Banded at Pow
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Birds of Pennsylvania
HAAS, Franklin; BURROWS, Roger
Avian Ecology And Conservation: A Pennsylvania Focus With National Implications- HC
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Birds of Central Pennsylvania - PB
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