Bridson 1978 - Bridson DM (1978) Studies in Pavetta (Rubiaceae subfam. Cinchonoideae) for Part 2 of 'Flora of Tropical East Africa: Rubiaceae'. Kew Bulletin 32(3): 609-652. doi: 10.2307/4109670.
There is no corrections for Pavetta crebrifolia var. pubescens yet.