Africa, H. d. R. (1977). Chemical investigation of allamanda cathartica cv. 'double yellow bell' [microform]. Photoduplication Service. University of the Philippines Library.
Chicago-referens (17:e uppl.)Africa, Helena del Rio. Chemical Investigation of Allamanda Cathartica Cv. 'Double Yellow Bell' [microform]. Quezon city: Photoduplication Service. University of the Philippines Library, 1977.
MLA-referens (9:e uppl.)Africa, Helena del Rio. Chemical Investigation of Allamanda Cathartica Cv. 'Double Yellow Bell' [microform]. Photoduplication Service. University of the Philippines Library, 1977.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.