M. Ibrahim Over the past decades the humid tropics of Costa Rica had been deforested mainly for cattle ranching . ... and productivity of grass legume mixtures , management of trees ( Gliricidia sepium and Erythrina berteroana etc. ) ...

Lucas H.L ( 1957 ) Extra - period latin - square change - over designs . Journal of Dairy Science ( EE.UU. ) 40 : 225239 . Lucas H.L ( 1983 ) Desing and analysis of feeding experiments with milking dairy cattle .