White, R.O. <br/><br/>
Ploughman wise, plougman foolish. 

 - London-CA :   British farm mechanization,   1950. 
 - páginas 4-5 :   ilustraciones blanco y negro 
 - Irregular 
 - Vol. 2, no.10 (Jan.1950) 
 - British farm mechanization. A link between British engineering and world farming ;   no.10 .
 - British farm mechanization. .