Assertion: lignin's unit | /r/HasProperty | lee
Facets:
Source sentences:
text: Itho et al. 1993; Johansson et al. 2002) and the formation of UV/VIS-absorbing stilbenes from phenylcoumaran ( -5) and 1,2-diarylpropane units ( -1) (Lee et al. 1990; Wu et al. 1991).