@article {stewart2006influence,
	title = {The influence of lignin chemistry and ultrastructure on the pulping efficiency of clonal aspen (Populus tremuloides Michx.)},
	journal = {Holzforschung},
	volume = {60},
	number = {2},
	year = {2006},
	pages = {111{\textendash}122},
	author = {Stewart, Jaclyn J and Kadla, John F and Mansfield, Shawn D}
}
