@article {2017,
	title = {Church Foundation and Parish Formation in Frisia in the Tenth and Eleventh Centuries. A Planned Development?},
	journal = {The Medieval Low Countries},
	volume = {4},
	year = {2017},
	pages = {1-55},
	author = {Langen, Gilles J. de and Mol, J.A.(Hans)}
}
