Fig. 1From: Comparison of methodologies used to determine aromatic lignin unit ratios in lignocellulosic biomassAromatic region of through-space two-dimensional 13C–13C correlation data on a 13C-enriched poplar woody stems and b 13C-enriched Monterey pine. 13C chemical shifts and approximate linewidths were extracted from the data and listed in grey and red text next to aromatic lignin unit chemical structures shown in cBack to article page