APA Style

Burtt, B, L., Weber, A. (1997). Revision of the genus Ridleyandra (Gesneriaceae) . Berlin: Duncker and Hublot.

MLA Style

Burtt, B., L.., Weber, A.. "Revision of the genus Ridleyandra (Gesneriaceae)". Berlin: Duncker and Hublot, 1997. Text.