APA

Graham A., .Studies in neotropical paleobotany. VIII. the Pliocene communities of Panama-introduction and ferns, gymnosperms, angiosperms. : .

Chicago

Graham Alan, .Studies in neotropical paleobotany. VIII. the Pliocene communities of Panama-introduction and ferns, gymnosperms, angiosperms. : .

Harvard

Graham A., .Studies in neotropical paleobotany. VIII. the Pliocene communities of Panama-introduction and ferns, gymnosperms, angiosperms. : .

MLA

Graham Alan, .: . .