Flight identification of European raptors / 
R.F. Porter...[et al.]. 
 - [3rd ed.]. -- 
 -- Calton :   T&AD Poyser,   1981 
 - 180 p., [48] h. de fot. 
<br/><br/>ISBN 0-85661-027-5 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Rapaces
<br/><br/><label>Universal Decimal Class. No.: </label>598.279(4)