Distribution map of <i>Sphrypicus ruber</i>
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Eric L. Walters, Edward H. Miller und Peter E. Lowther:  <i>Red-breasted Sapsucker (Sphyrapicus ruber)</i>. IN: The Birds of North America Online (A. Poole, Ed.). Ithaca: Cornell Lab of Ornithology; Retrieved from the Birds of North America Online 2002 (ohne Seitenangaben)