The authors regret that there was an error in the affiliation details for Prashant Kaushik in their original paper and apologise for any inconvenience caused. Prashant Kaushik should have been listed as ‘Independent Researcher, Kurukshetra, India’. The author would like to acknowledge the UPV Universitat Politècnica de València's digital libraries and databases that played a key role in the conceptual stages of the project. The author details have been updated in the online version of the paper.

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