Modell, H. (1950). Tertiäre Najaden V. <em>Archiv für Molluskenkunde.</em> 79(1/3): 37-44. page(s): 41-42, pl. 8, fig. 15, pl. 9, fig. 4 [details] Available for editors
MolluscaBase eds. (2025). MolluscaBase. Ptychobranchus langeckeri Modell, 1950 †. Accessed through: Marine Species Traits editorial board (2025) Marine Species Traits at: https://www.marinespecies.org/traits/aphia.php?p=taxdetails&id=1565143 on 2025-09-11
Marine Species Traits editorial board (2025). Marine Species Traits. Ptychobranchus langeckeri Modell, 1950 †. Accessed at: https://www.marinespecies.org/traits/aphia.php?p=taxdetails&id=1565143 on 2025-09-11
original descriptionModell, H. (1950). Tertiäre Najaden V. <em>Archiv für Molluskenkunde.</em> 79(1/3): 37-44. page(s): 41-42, pl. 8, fig. 15, pl. 9, fig. 4 [details] Available for editors