@inproceedings{BX-2015-JohnsonR,
	author        = "Michael Johnson and Robert Rosebrugh",
	booktitle     = "{Proceedings of the Fourth International Workshop on Bidirectional Transformations}",
	editor        = "Alcino Cunha and Ekkart Kindler",
	openpdf       = "http://ceur-ws.org/Vol-1396/p1-johnson.pdf",
	pages         = "1--15",
	publisher     = "{CEUR-WS.org}",
	series        = "{CEUR Workshop Proceedings}",
	title         = "{Spans of Delta Lenses}",
	url           = "http://ceur-ws.org/Vol-1396/#p1-johnson",
	volume        = 1396,
	year          = 2015,
}