Lorence, D. (2009). Lectotypification of Didymaea mexicana Hook. f. (Rubiaceae, Rubieae) and the identity of D. alsinoides (Schltdl. & Cham.) Standl.
Chicago-viite (17. p.)Lorence, David. Lectotypification of Didymaea Mexicana Hook. F. (Rubiaceae, Rubieae) and the Identity of D. Alsinoides (Schltdl. & Cham.) Standl. 2009.
MLA-viite (9. p.)Lorence, David. Lectotypification of Didymaea Mexicana Hook. F. (Rubiaceae, Rubieae) and the Identity of D. Alsinoides (Schltdl. & Cham.) Standl. 2009.
Varoitus: Nämä viitteet eivät aina ole täysin luotettavia.
