Steiner Kurt G <br/><br/>
On Farm Experimentation Handbook For Rural Development Projects Guidelines For The Development Of Ecological And Socioeconomic Sound Extesion Messages For Small Farmers 

 -  Eschborn : Gtz 1987. 
 - 307 
<br/><br/><br/>Eng 
<br/><br/><label>ISBN: </label>3880853428 (Pbk)