As a freelancer on assignment with New York City trade-book publishers, I edited most of an entire young-adult science series by the prolific Dr. Isaac Asimov for Walker Publishing and Avon/Camelot. In those days, manuscript editors worked with red pencil on hard copy, attaching queries and comments to the pages with stick-on "flags." Quite a few of my comments were about correcting the great professor's arithmetic.

Here are a few of the titles in his "How Did We Find Out About" series that I edited in the late 1970s and early 1980s:

		… and so on: … Oil, Gems, Vitamins, Energy, Nuclear Power, Outer Space, Our Human Roots, Coal, …