(B. R. ) ex Bitter, ?Repert. Spec. Nov. Regni Veg. 15: 153. 1918.?, 1918.

(B. R. ) ex Bitter and ex Bitter, (B. R. ), ?Abh. Naturwiss. Vereins Bremen 21: 282. 1912?, 1912.

(B. R. ) ex Bitter and ex Bitter, (B. R. ), ?Sp. Pl. 1: 184.?, 1753.