Verdc. (K.Schum. & K.Krause) 1979 - Verdcourt B (1979) Notes on African Rubiaceae: Leptactina and Cuviera. Kew Bulletin 33(3): 491-498. doi: 10.2307/4110148.
There is no corrections for Leptactina delagoensis subsp. bussei yet.