REFERENCES
- CAMPOS, T Dos, CANECHIO FILHO, V (1987) Principals culturas II. Instituto Campineiro de Ensino Agrícola, Campinas; São Paulo, Brazil; 401 pp (2nd edition).
- FREE, J B (1993) Insect pollination of crops. Academic Press; London, UK; 684 pp (2nd edition).
- JAYCOX, E R (1970) Ecological relationships between honey bees and soybeans. American Bee Journal 110: 306–307, 343–345, 383–385.
- ROBERTS, R B (1979) Spectrophotometric analysis of sugars produced by plants and harvested by insects. Journal of Apicultural Research 18(3): 191–195.