[2019-07-08]. (原始内容存档 (PDF)于2019-07-15). Matt Coler. A Grammar of Muylaq' Aymara Aymara as spoken in Southern Peru. : P. 33-34 [2019-07-08]. ISBN 978-90-04-28400-5
Genus Is No Longer Monotypic: A Second Species of Pachycaulos (Gesneriaceae) from the Huancabamba Depression in Northern Peru. Systematic Botany. 48(3);