Carlson, Rolf; Nilsson, Asa; Stroemqvist, Mats
Acta Chemica Scandinavica, Series B: Organic Chemistry and Biochemistry, 1983 , vol. 37, # 1 p. 7 - 14

Burger, Klaus; Wassmuth, Ulrike; Hein, Friedrich; Rottegger, Silvia
Liebigs Annalen der Chemie, 1984 , # 5 p. 991 - 1002