6C40:
reference: Site-Specific Incorporation of a Cu(2+) Spin Label into Proteins for Measuring Distances by Pulsed Dipolar Electron Spin Resonance Spectroscopy., Merz GE, Borbat PP, Muok AR, Srivastava M, Bunck DN, Freed JH, Crane BR, J Phys Chem B. 2018 Oct 3. doi: 10.1021/acs.jpcb.8b05619. PMID: 30222354

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