Ipomoea batatilla:

Ipomoea batatilla:

Ipomoea batatilla (Kunth) G. Don, Convolvulaceae: See Ipomoea carnea Jacq. subsp. fistulosa (Mart. ex Choisy) D. F. Austin.

I have no articles for this botanical term, but there might be some for the next level down (if found).