Bibliografía (15 obras)
Things precious & wild
1990
Encyc North Amer Birds
1989
On Watching Birds
The Audubon Society encyclopedia of North American birds
1980
From Laurel Hill to Siler's Bog
1969
The walking adventures of a naturalist
From Laurel Hill to Soler's Bog
Flashing wings
1968
The Audubon Nature Encyclopedia; Volume 1, Ac - Be
1965
Discovery; great moments in the lives of outstanding naturalists
1961
The wonders I see
1960
The Audubon book of true nature stories
1958
Songbirds in your garden
1953
