Não informado. (1931). Journal of the Rubber Research Institute of Malaya. Rubber Research Institute of Malaysia.
Chicago-referens (17:e uppl.)Não informado. Journal of the Rubber Research Institute of Malaya. Kuala Lumpur: Rubber Research Institute of Malaysia, 1931.
MLA-referens (8:e uppl.)Não informado. Journal of the Rubber Research Institute of Malaya. Rubber Research Institute of Malaysia, 1931.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.