Humphreys, L. R. <br/><br/>
Tropical pasture seed production / 
by L.R. Humphreys and F. Riveros. 
 - Rev. ed. 
 - Rome :  Food and Agriculture Organization of the United Nations,  1986, c1978. 
 - 203 pages  ill. ;  30 cm. 
 - FAO plant production and protection paper ;  8 .