"Havardia Small". Germplasm Resources Information Network. United States Department of Agriculture. 1999-03-05. Diarsipkan dari versi asli tanggal 2009-05-06. Diakses tanggal 2009-09-24.
"Species Records of Havardia". Germplasm Resources Information Network. United States Department of Agriculture. Diarsipkan dari versi asli tanggal 2008-10-15. Diakses tanggal 2009-09-24.
web.archive.org
"Havardia Small". Germplasm Resources Information Network. United States Department of Agriculture. 1999-03-05. Diarsipkan dari versi asli tanggal 2009-05-06. Diakses tanggal 2009-09-24.
"Species Records of Havardia". Germplasm Resources Information Network. United States Department of Agriculture. Diarsipkan dari versi asli tanggal 2008-10-15. Diakses tanggal 2009-09-24.