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James D. Sutherland, Orhi Barroso-Gomila and Rosa Barrio (2019). Biotin-based Approaches for the Study of Ubiquitin and Ubiquitin-like Protein Modifications. SUMOylation and Ubiquitination: Current and Emerging Concepts, Caister Academic Press, Pages 101-122. ISBN 978-1-912530-12-0.

DA Pérez Berrocal, KF Witting, H Ovaa and MPC Mulder (2020). Hybrid Chains: A Collaboration of Ubiquitin and Ubiquitin-Like Modifiers Introducing Cross-Functionality to the Ubiquitin Code. Front. Chem. 7:931.