Using the "box" in IRAS colours -0.7 < [25-12] < -0.3 and 0.0 < [60-25] < 0.25 (Gregorio-Hetem et al. 1993), 280 candidates to be LRG were selected from the IRAS PSC I and II (Joint IRAS Science Working Group 1985 & 1988).
Spurious objects were avoided by retaining only sources having good quality IRAS measurements. All sources previously identified as early-type stars, extragalactic or non-stellar objects were not considered.
The observations were collected at the Laboratório Nacional de Astrofısica (LNA), Brazil; European Southern Observatory (ESO), Chile and Observatoire de Haute Provence (OHP), France.
The northern hemisphere observations were developed at OHP by using
the AURELIE high resolution spectrometer (Gillet et al.
1994) at the 1.52 m coudé Telescope.
The observations cover the spectral range 
, with spectral
resolution of 0.02 nm.
The southern candidates were observed at LNA and ESO.
At LNA spectra were obtained at the coudé
focus of the 1.6 m telescope, using a GEC CCD covering the spectral
range 
, with spectral resolution of 0.3 Å.
The ESO observations were collected at the 1.52 m ESO telescope
with the Boller & Chivens Spectrograph and a CCD FA2K, using the
grating 
, which gives a resolution of 
in the spectral range 
.
We have observed 158 IRAS sources in the period 1994-1996. In the case of IRAS sources associated to two stars, both were observed so that the total sample includes 164 stars.