The American grouse and their identification.
{{cite web | url=http://www.europeana.eu/resolve/record/08701/5C946A1E2C19AC75590872DBA37EB56733F8D52B|title=The American grouse and their identification.|author=Shufeldt, Robert W.|accessdate=2013-05-20 |publisher=Europeana}}
<ref>{{cite web | url=http://www.europeana.eu/resolve/record/08701/5C946A1E2C19AC75590872DBA37EB56733F8D52B|title=The American grouse and their identification.|author=Shufeldt, Robert W.|accessdate=2013-05-20 |publisher=Europeana}}</ref>