Nc. Wickramasinghe et al., An integrated 2.5-12.5 mu m emission spectrum of naturally-occurring aromatic molecules, ASTRO SP SC, 268(1-3), 1999, pp. 317-320
The expected emission features from an ensemble of naturally-occurring arom
atic molecules is shown to be in satisfactory agreement with the emission p
roperties of 'PAH molecules' associated with planetary nebulae.