Low resolution spectroscopy of hot post-AGB candidates?

Abstract. Spectral types are determined from low resolu-tion optical spectra of 40 IRAS sources with far-infrared colours similar to planetary nebulae. The presence of cir-cumstellar dust, high galactic latitude, and early super-giant or giant spectral type, sometimes with emission in the Balmer lines, indicate that some of these stars are low mass stars in the post-AGB stage of evolution