Physical, Chemical and Pharmacological Characterization of a New Oleogel-Forming Triterpene Extract from the Outer Bark of Birch (Betulae Cortex) - Laszczyk, Melanie; Jäger, Sebastian; Simon-Haarhaus, Birgit; Scheffler, Armin; Schempp, Christoph M (Planta Medica, 2006)