(B. ) Bitter and Bitter, ?Abh. Naturwiss. Vereine Bremen 24: 473. 1919.?, 1919.

(B. ) Bitter, Bitter, (B. ), Bitter, (W. ), Bitter, (L. K. S. )&, Bitter, (B. ), Bitter, (B. S. )&, Bitter, (B. ), Bitter, (K. S. L. )&, Bitter, (B. ), Bitter, (B. ), Bitter, (W. ), and Bitter, (B. ), ?Abh. Naturwiss. Vereine Bremen 24: 504. 1919.?, 1919.

(B. ) Bitter, ?Abh. Naturwiss. Vereine Bremen 24: 465. 1919.?, 1919.