Rising, J. D. (2001). Geographic variation in size and shape of savannah sparrows, Passerculus sandwichensis. Cooper Ornithological Society.
Chicago-referens (17:e uppl.)Rising, James D. Geographic Variation in Size and Shape of Savannah Sparrows, Passerculus Sandwichensis. Riverside: Cooper Ornithological Society, 2001.
MLA-referens (9:e uppl.)Rising, James D. Geographic Variation in Size and Shape of Savannah Sparrows, Passerculus Sandwichensis. Cooper Ornithological Society, 2001.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.