@article {Abreu:1991pr,
	title = {{Searches for heavy neutrinos from Z decays}},
	journal = {Phys. Lett.},
	volume = {B274},
	year = {1992},
	pages = {230-238},
	doi = {10.1016/0370-2693(92)90528-C},
	author = {Abreu, P. and others}
}
