In a large warm bowl, dissolve yeast in very warm water.
In a 1 quart saucepan heat milk until a rim of tiny bubbles forms around side of pan. Stir in 4 tbls butter, sugar and salt; cool to lukewarm.
Pour lukewarm milk mixture into dissolved yeast along with egg. Gradually add half the flour, beating hard with a wooden spoon or electric mixer at medium speed for 3 to 5 minutes.
Add wheat germ, raisins, lemon rind and remaining flour a little at a time, to make a moderately stiff dough. Scrape down side of bowl. Sprinkle surface of dough with oil. Cover and let rise in warm place for about 1 ½ hours.
Punch down dough. Turn out onto lightly floured board and divide into 24 equal pieces. Shape dough into rounds and place about 1 inch apart in 3 greased, 8 inch round baking pans.
Brush with remaining melted butter and let rise in warm place for 30 to 40 minutes.
Beat egg yolk with 2 tbls water and brush surface of buns. Bake buns in preheated 400 degree oven about 20 minutes until golden brown.
Remove from oven and cool.
Combine powdered sugar and 2 tbls water until smooth. Decorate each in a cross pattern with sugar icing while buns are still warm.