1. H. P. Lotz, Trans. Am. Math. Soc. 211, 85–100 (1975).
2. D. I. Cartwright, Mem. Am. Math. Soc. 164, 1–48 (1975).
3. R. Haydon, Math. Z. 156, 19–47 (1977).
4. J. Lindenstrauss and L. Tzafriri, Adv. Math. 7B, 489–498 (1981).
5. P. J. Mangheni, Isr. J. Math. 48, 341–347 (1984).