###Instruction: Multi-class classification, answer with one of the labels:['no_consensus', 'delete', 'keep', 'comment', 'merge', 'redirect'] : ###Input:  Q124270709: disturbance variable (Q124270709) : in control engineering, a variable that has a disturbing effect on the controlled variable : ( delete | history | links | entity usage | logs ) Notability? Dorades ( talk ) 23:17, 3 February 2024 (UTC) Definitely notable, since it is a central concept in control theory, which should be able to easily be referenced (how?). German Wikipedia has a good article which sets it in the context with other central variables of control theory: [1] By a quick search, some external sources which mention the disturbance variable are: hawe fluid lexicon VICAIRE - Module 1B - Chapter 1 - BASIC CONCEPTS OF THE SYSTEMS' THEORY Sauer202 ( talk ) 08:24, 4 February 2024 (UTC)