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Manuscript Preparation, Copyediting, and Proofreading
Q. Can you recommend a best practice for dealing with URLs that are so long that they must break at the end of a line? This is primarily for a printed journal (thus short lines). If I allow the software to hyphenate the URL, it introduces a potentially confusing hyphen. If I force a line break, can I assume my reader will understand that it is all one looong URL? Thank you for your time.
A. Just as you say, URLs should be broken so as not to introduce any ambiguity. A hyphen or period at the end of a line, for instance, can confuse readers. Break after a colon or double slash but before most other punctuation. Please see CMOS 14.18 for details and examples.