1. Ahl, D.E., Gower, S.T., Mackay, D.S., Burrows, S.N., Norman, J.M., and Diak, G.R. 2004. Heterogeneity of light use effici cy in a northern Wisconsin forest: Implications for modeling net primary production with remote sensing. Remote Sensing of Environment, 93(1/2), 168–178.