The stellar spectra service is a compilation of several libraries
distributed by large observatories, which are intended to calibrate
telescopic observations. It currently provides access to two libraries
of reference stars distributed by ESO (composite spectra:
https://www.eso.org/sci/observing/tools/standards/IR_spectral_library.html)
and NASA IRTF (observations from SpeX:
http://irtfweb.ifa.hawaii.edu/~spex/IRTF_Spectral_Library/References_files/All.html).
