1           2001-04-18.23  Stephens 
2           1984-04-11.24  
3           1988-12-22.43  Weidenschilling et al. (1990) 
4           1988-12-23.21  Weidenschilling et al. (1990) 
5           1988-12-24.32  Weidenschilling et al. (1990) 
6  1998-08-27--2012-04-01  Lowell