@article {Lloyd2002IJRS,
	title = {{Deriving DSMs from LiDAR data with kriging}},
	journal = {International Journal of Remote Sensing},
	volume = {23},
	number = {12},
	year = {2002},
	pages = {2519-2524},
	author = {Lloyd, C.~D. and Atkinson, P.~M.}
}