@article {Heiskanen:October 1997:0304-3959:37,
	author = "Heiskanen T.",
	author = "Kalso E.",
	title = "Controlled-release oxycodone and morphine in cancer related pain",
	journal = "Pain",
	volume = "73",
	year = "October 1997",
	abstract = "",
	pages = "37-45(9)",
	url = "http://www.ingentaconnect.com/content/els/03043959/1997/00000073/00000001/art00072"
	doi = "doi:10.1016/S0304-3959(97)00072-9"
}