Smith, J. <br/><br/>
Production risk and optimal fertilizer rates :  an application of the random coefficent model / 
J. Smith and G. Umali. 
 - Manila :  International Rice Research Institute,  1985. 
 - 13 p. :  ill. ;  28 cm. 
 - IRRI research paper series ;  no. 115 .
<br/><br/> Cover title. 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Fertilizers.<br/>Rice--Fertilizers--Mathematical models.<br/>Crop yields--Mathematical models.