APA

Heusden E. C. H. V., Akkermans R. W. a. P. & Berg C. C.Cecropiaceae : Coussapoa and Pourouma, with an introduction to the family. : .

Chicago

Heusden E C H Van, Akkermans R W a P and Berg Cornelis C.Cecropiaceae : Coussapoa and Pourouma, with an introduction to the family. : .

Harvard

Heusden E. C. H. V., Akkermans R. W. a. P. and Berg C. C.Cecropiaceae : Coussapoa and Pourouma, with an introduction to the family. : .

MLA

Heusden E C H Van, Akkermans R W a P and Berg Cornelis C.: . .