@article {pmid20625442,
	title = {Generalized Multilevel Functional Regression},
	journal = {J Am Stat Assoc},
	volume = {104},
	number = {488},
	year = {2009},
	month = {Dec},
	pages = {1550{\textendash}1561},
	author = {Crainiceanu, C and Staicu, A. M. and Di, C.Z.}
}
