History. 

 - Londres-ENK :   International Institute for Conservation,   1975.. 
 - páginas 36-40 
 - Irregular 
 - Vol. 12, no. 1(Sum.1975) 
 - Art and archaeology technical abstracts   ;   Vol. 12, no. 1 .
<br/><br/> General methods and techniques. 
<br/><br/><br/>Inglés.