Nakamura, Eiichi; Kuwajima, Isao
Chemistry Letters, 1983 , p. 59 - 62

Seebach, Dieter; Weller, Thomas; Protschuk, Gerd; Beck, Albert K.; Hoekstra, Marvin S.
Helvetica Chimica Acta, 1981 , vol. 64, # 3 p. 716 - 735