Crop science and technology 
Gregorio, Geronimo L. 
 - revised edition. 
 -  Seguiban Printing and Publishing Enterprises, Inc.,  2016 
 - 265 pages. 
978-9-71040619-7
Agricultural technology.
HS 631.558 G821 2016
                        978-9-71040619-7
Agricultural technology.
HS 631.558 G821 2016