1           1977-04-11.23  
 2           1991-09-10.99  Shevchenko et al. (1992) 
 3           1991-09-12.02  Shevchenko et al. (1992) 
 4           1991-09-13.95  Shevchenko et al. (1992) 
 5           1991-10-06.77  Shevchenko et al. (1992) 
 6           1991-10-11.88  Shevchenko et al. (1992) 
 7           1991-11-01.80  Shevchenko et al. (1992) 
 8           2011-05-21.94  
 9           2011-05-22.94  
10           2011-05-23.93  
11           2011-04-09.94  
12           2011-04-10.96  
13  1998-12-02--2011-07-28  Lowell