Authors: Ullmann, U Lehnfeld, R Bliesath, H Birkel, M Gebbing, H Grave, M Wolf, H

Citation: U. Ullmann et al., Relative bioavailability of imipramine (tofranil) coated tablets in healthy volunteers, INT J CL PH, 39(6), 2001, pp. 271-276

Authors: Popken, G Schultze-Seemann, W Seiler, KU Birkel, M Wetterauer, U

Citation: G. Popken et al., Intravesical administration of 5-aminolevulinic acid (5-ALA) - Safety and pharmacokinetics of 5-ALA and its metabolite protoporphyrin IX, EUR J CL PH, 56(3), 2000, pp. 241-246

Authors: Birkel, M Sarkar, S

Citation: M. Birkel et S. Sarkar, Extremely high energy cosmic rays from relic particle decays, ASTROPART P, 9(4), 1998, pp. 297-309