Smedegård-Petersen, V. The perithecial and pycnidial stages of Pyrenophora teres and P. graminea in Denmark Særtryk af FRIESIA X, 1-2 1972 - Copenhagen The Royal Vet. and Agri. University 1973 - 61-85 Subjects--Index Terms: Pathology PLANT DISEASES PATHOGENS