Ahti, T 1989: [Review of:] O. E. Eriksson & D. L. Hawksworth (eds.): Systema Ascomycetum Vol. 6. CAB International Mycological Institute and University of Umea, Kew and Umea. 1987. - Lichenologist21(2): 190. [RLL List # 138 / Rec.# 329] Keywords: REVIEW