Takeuchi, W. (2012)

Modern sequels to the Kaiserin-Augusta-Fluss itinerary of Carl Ledermann: Rhysotoechia welzeniana sp. nov. (Sapindaceae), a remarkable species from the upper Sepik of Papua New Guinea

. Phytotaxa 61 (1): 55–60. https://doi.org/10.11646/phytotaxa.61.1.5