Columbia subject headings:
Harvard subject headings:
Astronomical spectroscopy--Congresses
Galaxies--Congresses
Infrared astronomy--Congresses.
Interstellar matter--Optical properties--Congresses.
Princeton subject headings:
Astronomical spectroscopy--Congresses.
Galaxies--Congresses.
Infrared astronomy--Congresses.
Interstellar matter--Optical properties--Congresses.