Modell, H. 1943. Tertiäre Najaden III. Archiv für Molluskenkunde 75: 107-117. Available electronically.
Modell, 1931. Palaeontogr. 75: 71.
Modell, 1935. Arch. Moll. 67: 130.
Modell, 1943. Arch. Moll. 75: 109.
Modell, 1964. Arch. Moll. 93: 101.
Type species: Ptychorhynchoideus gümbeli Modell, 1931 (orig. desig.) = Ptychorhynchoideus guembeli
Modell, 1943. Arch. Moll. 75: 112.
Modell, 1964. Arch. Moll. 93: 91.
Type species: Ptychorhynchoideus kolasii Modell, 1931 (orig. desig.)
Modell, 1935. Arch. Moll. 67: 132, pl. 10, figs. 6-7.
Modell, 1943. Arch. Moll. 75: 114, pl. 1, figs. 6a-b.
Modell, 1943. Arch. Moll. 75: 111, pl. 1, figs. 3a-b.
Modell, 1931. Palaeontogr. 75: 71, pl. 13, fig.s 7-9; pl . 14, figs. 15d-f.
Modell, 1943. Arch. Moll. 75: 113, pl. 1, figs. 4a-c [as ‘Vanderschaliea kolasii’].
Modell, 1931. Palaeontogr. 75: 73, pl. 14, figs. 1-4, 15h-k.
Modell, 1943. Arch. Moll. 75: 114.
Modell, 1931. Palaeontogr. 75: 74, pl. 14, figs. 5-7, 14, 15n.
Modell, 1943. Arch. Moll. 75: 114.