Citation, Documentation of Sources

Q. I’m writing an essay based upon an early explorer’s daily journal and quote extensively from it—do I need to cite it every single time, or is there a way to just cite it once at the beginning and it will be understood that subsequent quotes are from the same source?

A. Luckily, you have the power to make it understood! For instance, you can write “All references to X’s journal are to this edition.” Citation styles aren’t meant to burden writers and readers with endless busywork. Rather, they’re a tool for conveying information accurately and concisely and consistently. When writing notes and bibliographies, try not to think “Aargh—do I have to follow all these rules?” but “How can I use these tools to support my point?”

[This answer relies on the 17th edition of CMOS (2017) unless otherwise noted.]