F. Flora Malesiana, ?Identification lists of Malaysian specimens: 42-46.?, Leyden, Foundation Flora Malesiana, 1972., pp. pp. 727-811, 1972.

N. K. B.  Robson, ?Identification lists of Malaysian specimens: 46. Hypericum.?, Leyden, Foundation Flora Malesiana, 1972., pp. pp. 801-811, 1972.