(B. ) Bitter, ?Repert. Spec. Nov. Regni Veg. 18: 307. 1922.?, 1922.

(B. ) Bitter, ?Repert. Spec. Nov. Regni Veg. 18: 315. 1922?, 1922.

(B. ) Bitter, ?Abh. Naturwiss. Vereine Bremen 24: 382. 1919.?, 1919.