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Citation, Documentation of Sources
Q. How does Chicago recommend citing a URL that is only accessible via a paywall? I’ve noticed the practice of including a parenthetical statement “(subscription required),” but I haven’t seen Chicago address this.
A. See CMOS 14.11. We suggest giving the name of the database rather than a URL in such cases. But your approach might work also. Beware, however, that noting it in one case somewhat implies that all sources have been checked for accessibility. That might oblige you to recheck all the sources.