During the past 20 years, infrared spectroscopy has become one of the most important tools for the quantitative analysis of organic compounds. The manufacturers of infrared spectrometers are constantly striving to increase the resolution and have succeeded remarkably well.
W. W. Hanneman, "Quantitative Analyses by Extremely Low-Resolution Infrared Spectroscopy," Appl. Spectrosc. 22, 572-574 (1968)