or result originating from the matrix, reagents and any residual bias
in the measurement device or process, which contributes to the value obtained for the quantity in the analytical procedure.
PAC, 1989, 61, 1657
(Nomenclature for automated and mechanised analysis (Recommendations 1989))
on page 1662
PAC, 1990, 62, 2167
(Glossary of atmospheric chemistry terms (Recommendations 1990))
on page 2176