Systematic notes on Palearctic birds. No. 4, The choughs (Pyrrhocorax). American Museum novitates ; no. 1658

Vaurie, Charles.2005-10-062005-10-061954http://hdl.handle.net/2246/35957 p. ; 24 cm.Includes bibliographical references.678708 bytesapplication/pdfen-USQL1 .A436 no.1658, 1954PyrrhocoraxChoughsSystematic notes on Palearctic birds. No. 4, The choughs (Pyrrhocorax). American Museum novitates ; no. 1658Choughs (Pyrrhocorax)Palearctic birds.text