@article {Elster:September 2005:0543-1972:883,
	author = "Elster, C.",
	author = "Woger, W.",
	author = "Cox, M.",
	title = "Analysis of Key Comparison Data: Unstable Travelling Standards",
	journal = "Measurement Techniques",
	volume = "48",
	year = "September 2005",
	abstract = "A procedure for the analysis of key comparison data is proposed in the case where the travelling standard shows a deterministic or random drift. It is assumed that some parametric model such as a linear trend is appropriate for modelling the deterministic part of the drift. The random part of the drift is assumed to be adequately described by a random walk model. The chosen drift model is determined by least squares and a model check is carried out. If the model check is satisfied, the derived drift model is applied to determine degrees of equivalence. A star-type sequence is required for the comparison in order to check the adequacy of the random drift model. The procedure is illustrated by its application to simulated data.",
	pages = "883-893(11)",
	url = "http://www.ingentaconnect.com/content/klu/mete/2005/00000048/00000009/00000239"
	doi = "doi:10.1007/s11018-005-0239-1"
}