Bridson DM (1985). "The reinstatement of Psydrax (Rubiaceae, subfam. Cinchonoideae tribe Vanguerieae) and a revision of the African species". Kew Bulletin. 40 (4): 687–725. Bibcode:1985KewBu..40..687B. doi:10.2307/4109853. JSTOR4109853.
Bridson DM (1985). "The reinstatement of Psydrax (Rubiaceae, subfam. Cinchonoideae tribe Vanguerieae) and a revision of the African species". Kew Bulletin. 40 (4): 687–725. Bibcode:1985KewBu..40..687B. doi:10.2307/4109853. JSTOR4109853.
Bridson DM (1985). "The reinstatement of Psydrax (Rubiaceae, subfam. Cinchonoideae tribe Vanguerieae) and a revision of the African species". Kew Bulletin. 40 (4): 687–725. Bibcode:1985KewBu..40..687B. doi:10.2307/4109853. JSTOR4109853.