Mass spectrometry

Schaaf, O.; Dettner, K.: Transformation of steroids by Bacillus strains isolated from the foregut of water beetles (Coleoptera: Dytiscidae): I. Metabolism of androst-4-en-3,17-dione (AD). Journal of Steroid Biochemistry and Molecular Biology 67 (5-6), pp. 451 - 465 (1998)