At least 1 1/2 hours before serving, peel and section the oranges. With a serrated knife or citrus knife, remove the membrane lining from each orange segment. Place oranges in a bowl and squeeze all excess juice from the remaining lining over the oranges. Discard any membrane and pick out seeds, if necessary. Drizzle honey and sprinkle cinnamon over oranges, cover and let stand at room temperature for at least 1 hour. Clean greens and pat dry. Break into bite size pieces and toss well with onions, radishes and nuts in a large bowl. Drizzle olive oil over salad and toss to distribute. Season to taste with salt and freshly ground pepper. Just before serving, add the oranges and all their liquid. Mix well.