• A secondary source is one where the author of the work you are reading (e.g. book, article, etc.) is referencing or quoting another author's work.
• ACS style does not recommend citing secondary sources. Whenever possible, locate the original source of information cited in a work you have read, and cite the original source.
• If an original source cannot be located, it should not be cited, and the secondary source should be cited instead.
For ease of use, this guide divides Works Cited list entries into different formats.
Select the format you require from the Reference List Entries menu or use the links below: