http://www.loc.gov/mods/v3 http://www.loc.gov/standards/mods/v3/mods-3-2.xsd
Natural control of Helicoverpa armigera in smallholder crops in East Africa
233 pages : illustrations, maps ; 24 cm.
doctoral Landbouwuniversiteit te Wageningen 1993.
Includes bibliographical references (pages [221]-232).