TY - JOUR AN - 5 AU - Björkman,O.. AU - Demmig-Adams,B.. TI - Photon yield of oxygen evolution and chlorophyll fluorescence characteristics ar 77 K among vascular plants of diverse origin. JO - Planta PY - (1987) VL - 170 SP - 489-504 M2 - 489 DO - 10.1007/BF00402983 ER -