A Soil And Plant Analysis Manual Adapted For The West Asia And North Africa Region /

by Ryan, John.
Published 1996

Fertilizer Use Efficiency Under Rain-Fed Agriculture In West Asia And North Africa /

by Ryan, John.
Published 1991

Soil Test Calibration In West Asia And North Africa /

by Ryan, John.
Published 1987

Accomplishments And Future Challenges In Dryland Soil Fertility Research In The Mediterranean Area /

by Ryan, John.
Published 1997