Não informado. (1909). Circular of the Department of Agriculture, Trinidad and Tobago. Circular of the Department of Agriculture.
Chicago-viite (17. p.)Não informado. Circular of the Department of Agriculture, Trinidad and Tobago. Port of Spain: Circular of the Department of Agriculture, 1909.
MLA-viite (8. p.)Não informado. Circular of the Department of Agriculture, Trinidad and Tobago. Circular of the Department of Agriculture, 1909.
Varoitus: Nämä viitteet eivät aina ole täysin luotettavia.