Yi, Xianfeng <br/><br/>
Manipulation of walnuts to facilitate opening by the great spotted woodpecker (Picoides major): is it tool use?  [electronic resource] 

 -  Animal cognition  Jan 2014 
 - 157-61 p.  digital 
<br/><br/> Publication Type: Journal Article; Research Support, Non-U.S. Gov't 
<br/><br/><label>ISSN: </label>1435-9456 
<br/><br/><label>Standard No.: </label>10.1007/s10071-013-0695-y  doi 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Animals<br/>Birds<br/>Feeding Behavior--psychology<br/>Juglans<br/>Nuts<br/>Tool Use Behavior