1 1990-08-22.31 Lagerkvist et al. (1992) 2 1990-08-24.18 Lagerkvist et al. (1992) 3 1990-08-26.23 Lagerkvist et al. (1992) 4 1990-08-28.20 Lagerkvist et al. (1992) 5 1990-09-12.21 Gil-Hutton (1992) 6 1990-09-12.07 Gil-Hutton (1992) 7 1990-09-12.33 Gil-Hutton (1992) 8 1990-09-12.46 Gil-Hutton (1992) 9 1993-05-14--2012-04-15 Lowell