Optical data on cryogenic ices
N
2
Grundy, Schmitt, and Quirico 1993,
Icarus
105,
254-258.
H
2
O
Grundy and Schmitt 1998,
J. Geophys. Res.
103,
25,809-25,822.
CH
4
Grundy, Schmitt, and Quirico 2001,
Icarus
155,
486-496.
Lots more on the way...