@article {334,
	title = {Global and local kernel methods for approximating derivatives on the sphere},
	journal = {Dolomites Research Notes on Approximation},
	volume = {6},
	year = {2013},
	publisher = {Padova University Press},
	address = {Padova, IT},
	issn = {2035-6803},
	author = {Grady Wright}
}