ANGULAR ORIENTATION OF THE STABLE TYROSYL RADICAL WITHIN PHOTOSYSTEM-II BY HIGH-FIELD 245-GHZ ELECTRON-PARAMAGNETIC-RESONANCE - UN, S; BRUNEL, LC; BRILL, TM; ZIMMERMANN, JL; RUTHERFORD, AW (PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 1994)